♪ you'll be the prince and i'll be the princess ♪ ♪ it's a love story >> we're a fantastic team. >> now, so does the rest of the world. tonight on a special "20/20" we're here in london with wedding mania. guessing the guests, but now no guessing who's walking meghan down the aisle. >> prince charles is stepping in. >> prince harry and the love story that spans from mother to marriage. >> without question i think she would be best friends with meghan. >> the two women in his life. one shy at first. >> as far as i was concerned i was a fat chubby 20-year-old. >> one already shining in the spotlight. >> i am proud to be a feminist. >> both shaking up the royal family tree.

>> meghan is someone who like diana leads with the heart. >> but now from the people's princess to an american princess. >> waiting to find the right person, someone willing to take on the job. >> the looks. ♪ >> the look alikes. >> for just a second did you think it was the real person? >> the one thing everyone will be looking at, the dress. meghan wore this on tv. >> i do. >> but what will she wear tomorrow morning? >> we're stuck together to the rest of our life. ♪ baby just say yes >> now david muir and robin roberts. >> good evening everyone. we're waiter to prince harry and meghan markle to say i do. >> as you're watching us in america, it's wedding day in england. we found out a twist in the

wedding plans. >> that's right. meghan markle will walk into the chapel on her own, but halfway down the aisle prince charles will be waiting ready to escort her the rest of the way to her prince. >> some experts said he always wanted a daughter. now he has a chance to walk his soon to be daughter in law down the aisle. >> so many will be watching, will also be thinking of someone else, the late princess diana. she won over the world. now the american princess with her own voice who won over the prince. ♪ ♪ you are the one i want >> harry and meghan's relationship really is a fairytale. ♪ i'll never let you go >> reporter: an elite few have had that dream come true -- the dream of marrying a prince. four decades ago it was princess diana and now it is american meghan markle. >> the relationship works with

harry, because i think probably harry recognizes something of his mother in her. >> reporter: princess diana and meghan markle born worlds apart they would never meet and yet, they're the two most influential and important women in prince harry's life. when the newest royal couple met times had changed significantly for the british monarchy. >> it makes me smile in a way. you want to listen very carefully when the choir's singing tomorrow, because there'll be another sound. and it'll be the sound of the duke of windsor, who's buried at frogmore quite nearby, spinning in his grave. >> reporter: that's because edward, the duke of windsor -- as portrayed in the netflix series, "the crown" -- abdicated the throne to marry his divorced, american fiancée wallis simpson. >> is she really worth it? >> i love her with all my heart.

>> reporter: that meant queen elizabeth's father was crowned king george. but that was 80 years ago when obligations to queen and country trumped marrying for love. >> it genuinely is a different age. >> reporter: andrew morton's latest book is titled, "meghan: a hollywood princess." >> we have a biracial, divorced woman about to become her royal highness. so it shows you how what a remarkable transformation we've seen in this reign. >> meghan is a feminist, part of the me too movement. >> there's no better time to shine a light on women feeling empowered. >> the words "breath of fresh air" is often used in connection with the royal family in terms of meghan markle. it's absolutely true. >> reporter: at 36, meghan is three years older than her husband-to-be. she was a successful actress with a dual degree in theater and international relations from northwestern university, when a friend set-up her up on a blind date with harry, prince of

wales. >> and so we went and had a -- met for a drink and then i think very quickly into that we said, well, what are we doing tomorrow? we should -- we should meet again. >> reporter: the couple wasted little time. within weeks they traveled to africa for their third date. >> africa is somewhere that has been really important to harry all of his life. and has been incredibly important in his and meghan's relationship. it was on a trip to botswana, just a few weeks after they met, that they really fell in love. >> reporter: meghan's royal "wooing" was far cry from harry's mother, lady diana spencer, who was a teenage nursery school teacher when she began seeing prince charles, heir to the british throne. >> they had met each other 13 times before they got engaged. she called him "sir," up until the point where they got engaged. >> prince charles, i think, was looking for more for a companion

to take on his duties than someone who would be a lover. >> what was your instant impression? >> i remember thinking what a very jolly and amusing and ayeye attractive 16-year-old she was. >> reporter: in their official engagement interview, a shy diana looks on as prince charles does most of the talking. >> until meghan came on the scene, a royal girlfriend would say nothing. and would go through the ordeal of the paparazzi, being chased down the street. >> diana felt she'd been thrown in the deep end. >> it was a challenge. >> reporter: diana would later discuss this in her famous bbc news panorama interview. >> i was very daunted because, as far as i was concerned, i was a fat, chubby 20-year-old -- 21-year-old -- and i couldn't understand the level of interest. the media were everywhere. it was isolating, but it was also a situation where you couldn't indulge in feeling sorry for yourself. you had to either sink or swim. and you had to learn that very

fast. >> reporter: at 20 years old, diana rose from relative obscurity to become the most photographed woman in the world. already in her mid-30s, meghan markle came into her engagement with media savvy, an actress and influencer with millions of social media followers. >> she's a woman who's very much at ease with herself, at ease with the camera. >> everything was just perfect. >> reporter: that was evident in their engagement interview as meghan and harry tell the story of his proposal. >> just a cozy night, it was -- what we were doing just roasting chicken and having -- >> roasting a chicken, trying to roast a chicken. >> trying to roast a chicken and it just -- just an amazing surprise, it was so sweet and natural and very romantic. he got on one knee. >> of course. >> was it an instant yes from you? >> yes, as a matter of fact i could barely let you finish proposing. i said, "can i say yes now?" >> she didn't even let me finish. then there was hugs. >> reporter: the engagement

>> reporter: the engagement ring a diamond from botswana and two from the collection of harry's mother diana. >> i think everything about harry's thoughtfulness is -- and the inclusion of that and obviously not being able to meet his mom. it's so important to me to -- to know that she's a part of this with us. >> william and harry have what is often called a "smiling hatred" of the media. they believe the media killed their mother. >> it's something they have to deal with. and for harry, it has to be a huge relief to finally meet somebody who's at ease in front of the cameras. >> reporter: joining the royal family means meghan must actually dial back her public presence, giving up her acting career and shutting down her personal social media accounts. >> she's given up an awful lot. and what does she get back in exchange? anything she gets involved in the world takes notice. so she can make a genuine difference. >> meghan is someone who, like

diana, is so strong-willed in her beliefs, who leads with the heart, who isn't afraid to speak her mind. >> harry really needed that person to marry. he needed a team member. and that's what meghan is. she's a team member in the most famous family in the world. >> reporter: coming up, that moment tomorrow marries her prince in st. george's chapel. >> the same venue where prince harry was baptized when he was just a few weeks old is the same venue where as a fully grown man, he gets married to the love of his life. ♪ music playing ♪ je plonge à l'envers attiré par l'extase ♪ ♪ un tourbillon vert illumine les sirènes ♪ ♪ ♪ oh la fête fo', fo' ♪ ♪ ♪ oui l'endorphine s'est envolée ♪ ♪

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>> reporter: princess diana and meghan markle.

before they were world famous, they were young girls playing dress up. never imaging their futures as real, live princesses. >> it's really hard not to draw parallels between meghan and diana. they both have this fantastic way of connecting with people. having this, sort of, magical touch with people. ♪ you're so gorgeous it actually hurts ♪ >> reporter: so much alike and yet worlds apart. from age two until she was around six meghan lived here, in this apartment above a garage, with her mother doria pictured here on instagram, in the middle class miracle mile neighborhood of los angles. >> meghan is the world's most famous valley girl. she was the product of a white, caucasian father and an african american mother who was a yoga

teacher and a social worker. >> she went to private schools. went to a private girls catholic school for high school. >> reporter: and after school meghan would often visit her father on the set where he worked on the long-running t-v show, "married with children." >> on the set of "married with children" every day for 10 years i was there. >> wow. >> i know it's a very perverse place for a little girl to grow up. >> i mean, diana's childhood was totally different to meghan's. diana lived in park house, next door to the queen's home of sandringham in norfolk. she had nannies. she had tutors. >> reporter: diana attended a girl's boarding school in switzerland and had dreams of being a ballet dancer. >> meghan was the bright girl in class. she says she was smart. she liked debate. she liked protest. she was articulate. >> reporter: andrew morton interviewed princess diana for his book, "diana: her true story." >> diana, as she said to me, you know, she was no great shakes academically. she was very shy. her idea of torment was having to go onstage in the christmas play. >> reporter: a far cry from

meghan who jumped at the chance to act in school productions at immaculate heart school in los angeles. but whether diana wanted to or not, at 20 she was thrust onto a global stage. 750 million people watched as she walked down the aisle of st. paul's cathedral to marry prince charles. escorting diana was her father earl spencer, still recovering from a stroke. and just this week the question of who will walk meghan down the aisle has become front page news. >> this morning kensington palace announcing that meghan markle has asked prince charles to accompany her down the aisle.

>> reporter: and when she does walk down the aisle it will be as a new kind a princess. one who has already had a career by her 30th birthday meghan was starring as a wise-cracking paralegal in the television series "suits." >> wow you're pretty good. you've hit on me. i wasn't hitting on you. trust me i'm not interested. >> reporter: she had married her long-time boyfriend, a movie producer named trevor engelson. diana, at 30, had two young children and a crumbling marriage which would end in divorce. >> divorce runs through the royal family now like a tide. >> three out of four of the queen's children got divorced. as a result, there is now more leeway in the royal family. william and harry are allowed to marry women they love. >> reporter: and while diana was >> reporter: and while diana was to able escape her unhappy marriage, tragedy would strike just two weeks shy of harry's 13th birthday. >> we have an update on the condition of diana the princess of wales who was involved in a car accident.

>> diana princess of wales has died. >> tragic death almost exactly 16 hours ago of diana. >> it's still hard to comprehend the extent to which princess diana's death affected, not just people in britain, but around the world. >> reporter: patrick jephson was princess diana's chief of staff for eight years. >> 21 years since that terrible day i have been constantly struck by wherever you go people will remember where they were when she died. >> reporter: the world mourned watching her devastated sons follow diana's coffin through the streets of london. >> i think losing your mother at such a young age does end up shaping your life massively. of course it does. >> for generations, royalty has held themselves in privacy. and here, harry has talked openly about the loss of his mother.

>> reporter: prince harry revealed his feelings in a recent bbc documentary entitled, "diana: seven days." >> i think one of the hardest things to come to terms with is the fact that the people that chased her through -- into the tunnel were the same people that were taking photographs of her while she was still dying in the back seat of the car. >> anybody who has experienced the loss of a parent at that sort of age would understand that the world can seem a very strange place and in some respects the intensity of grief and loss has a desensitizing effect. >> reporter: but he would soldier on. following royal tradition harry joined the army. he became a combat helicopter pilot and he would serve two tours in afghanistan. >> life in the army, as he has said, was very formative and gave him a sense of structure when he needed it. discipline when he knew he needed it. >> reporter: meghan would divorce her husband after only

two years of marriage. meanwhile harry watched his older brother william marry kate middleton and start their family. the three were often together at polo matches and doing charity work. >> he was always the third wheel on royal enjoyments. it was always the three of them on events and he didn't have anyone by his side and that began to matter. >> i've longed for kids since i was very very young. so i'm waiting to find the right person, someone who is willing to take on the job. >> reporter: and though the woman who is now taking on that role will never meet her mother-in-law, prince harry has said that his mother diana would most certainly approve. >> there is no doubt that princess diana would have wanted her children to marry for love. being royal can be very lonely and she would have wanted for her children somebody who could be a companion and an encouragement and a source of wisdom for them. >> reporter: next, we all

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♪ >> announcer: "20/20" continues with the royal wedding, legacy and love. >> reporter: these are the faces of the young royals who have captured the public's imagination. and are catapulting the monarchy into the 21st century. >> the future of the royal family will be shaped by what is now known as the fab four, the kind of royal beatles harry, william, meghan, and catherine. and they are seen as authentic stars. >> they have this energy that makes the royal family attractive, fun, and glamorous. >> reporter: a throwback to the 80s when there were four other young royals. prince charles, prince andrew, and their wives princess diana and sarah ferguson, the duchess of york. >> when sarah ferguson married into the royal family, as suddenly diana had some partners in crime all in their '20s. prince charles, heir to the

throne, a good decade older than them all, had to behave. on some levels, we had a fab four, but they weren't particularly functional. >> reporter: but it would be diana and sarah who would go on to steal the spotlight. even before sarah's wedding, the duo would break royal protocol making headlines in the tabloids. >> they both got dressed up as policewomen and crashed prince andrew's bachelor party. you're not supposed to do that. >> reporter: but both learned to adjust to life set by palace rules. >> this was a family that is not like any other family. they have all these rules, all these protocols. they were sort of thrown into the deep end really. >> reporter: as diana stated it during her famous bbc news panorama interview. >> no, no one sat me down with a piece of paper and said, "this is what is expected of you." >> we've laughed and smiled and cried and -- and every day sought each other's advice. >> reporter: and being only in their twenties, they sought to inject a bit of fun into their royal duties. >> when they're at royal ascot

which is very proper in the royal enclosure where you're wearing your hats and everything and they're poking friends with their umbrellas. not the done thing. >> reporter: and now a new generation of royal wives with new voices are becoming iconic in their own right and are captivating the world's attention. >> while william and harry have been the stars of the show when it came to the younger generation, for a long time, now it's their women who are really the focus of all our attention. >> kate, you're beautiful. >> reporter: kate and meghan are both 36. the duchess of cambridge nearly ten years older than diana at the time of her marriage. meghan a decade older than sarah. they had years to become independent women. >> they definitely have formed and will continue to form a close alliance, because they're in a very unique situation. >> catherine has been absolutely -- >> she's been wonderful. >> amazing, as has william as well, you know, fantastic support. >> this incarnation of the fab four, a lot more functional. you've got four people in their

mid-30s. laser focused on that they want to achieve. >> reporter: the four made their first joint public appearance on christmas day less than a month after the couple's engagement. meghan's mere presence was history-making. >> meghan, who is only just engaged to prince harry was allowed to attend church, curtsey to the queen in front of the world. the first time we ever saw her do that. >> reporter: and she did it in unison with kate. meghan already comfortable in front of the cameras has been picking up a few tips as she trades one public life for another. >> being a celebrity is something you work for. being a royal is something you're granted. so, knowing when to stop being a celebrity and start being a princess is critically important. >> i'd like to imagine meghan picks her brain, and asks her, you know, "when should i stand here? who should i let go before me? when do i curtsy?" >> reporter: and even for an actress already known for her style, some fashion advice. >> kate learned from the queen that you can put weights in dresses to make sure that they don't blow up with the wind, and

that's something that she will definitely have passed on to meghan. >> reporter: and perhaps all of that advice on protocol is working. meghan sitting there just like kate during the fab four's first engagement at the royal foundation. where they spoke about their hope for the future. >> we're really looking forward to working as a pair and as a four going forward and hoping to make as much of a difference where we can. >> reporter: and even some royal humor when asked do they ever disagree? >> oh, yes! the fact that everybody here is laughing means everybody knows exactly what it's like. but you know we're stuck together for the rest of our lives. >> togetherness at its finest. >> not every family gets along like that anyway. i mean, come on. even when you're not -- when you don't have all the -- all of the eyes of the world watching. so it's -- it's so lucky that they're all getting along so well. >> reporter: and conveniently the four are neighbors. >> because they're all based at kensington palace, there will be a lot of interactions that we won't know about. >> reporter: william and kate live in apartment 1a, more like

a four-story mansion. and harry and meghan just steps away in nottingham cottage for now, a two-bedroom home. and perhaps soon william and kate's children could have some new royal playmates. it's been harry's longtime wish. >> i can't wait for the day. it'll be fantastic. >> we know that meghan wants children. and i think that they will be looking to that pretty soon. >> reporter: and it will be important to raise his own children the way his mother raised him. he and his brother talked about this in an itv documentary on the 20th anniversary of diana's death. >> as a son, i will say she was the best mum in the world. she smothered us with love, that's for sure. >> but she understood that there was a real life outside of palace walls. >> reporter: as diana said in that panorama interview -- >> i want them to have an understanding of people's emotions, people's distress, people's hopes and dreams.

if the seed is there, then i hope it will grow because knowledge is power. >> reporter: and that seed has, in fact, blossomed into her sons' commitment to bring about change. >> we've all got that same passion to want to make a difference. >> i see the future of the royal family as being domestically william and catherine. in terms of the international perspective, henry or harry and meghan. >> you have to remember the queen is still figurehead to two billion people. that's a third of the world. she's not doing any long haul travel anymore. that's going on to meghan and harry. >> we're a fantastic team. we know we are, and we'll -- we hope to, you know, over time try and have as much impact for all the things that we care about as much as possible. >> i am very excited about that. >> reporter: when we come back princess diana's style evolution. and meghan markle's revolution. >> expect to see meghan push fashion boundaries. >> reporter: and a royal double-take, when we return. what seems to be the problem? just some cramps.... hold on! ugh, say it's like stabbing knives. sometimes i have to call in sick. any pelvic pain? kinda...

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>> announcer: now from buckingham palace, we continue with deborah roberts. >> i'm here in front of buckingham palace where a 15-year-old meghan markle was photographed as a tourist never imagining she would join the royal family. now she's being photographed on the world's stage and bringing a whole new dazzle to the windsor wardrobe. ♪ >> meghan markle, first self-made woman to ever enter in the royal family. so she's very definite in her style.

>> reporter: meghan markle has known from the beginning what looks good. she's been getting it right on red carpets for year on the scene at just 19, she was unschooled in the worldly ways. >> careful. >> she said to me, you know she had no smart dresses, no smart clothes and she very quickly had to get a wardrobe together. >> reporter: what a wardrobe that was. >> prince charles himself has taken a publicity backseat to his wife's trendsetting clothes. >> the di look is described as exciting, although it is in essence traditional and classic. whatever it is it is selling like hotcakes. as the years went on, after her divorce, as diana grew more confident in her personal life, she seemed to grow bolder in her fashion choices. >> you started seeing her in versace. some of those fabulously sexy outfits. i think everybody was amazed at diana's beauty. she became this style icon.

>> her choices of those dresses kind of gave us a new way of defining what royal glamour could be. >> reporter: amanda wakeley is one of the few designers who has dressed both diana and meghan. >> how would you compare her style and diana's style? >> i think diana really, really understood her own style and i think meghan really, in the same way, really owns her look, she knows what works on her. >> reporter: for meghan, her royal glamour starts with california casual. just ask her longtime friend and makeup artist daniel martin. >> what meghan's most comfortable in is a cashmere sweater and skinny jeans. meghan's personal style is very chic, very sophisticated, but still very understated. >> you know what nobody likes, nobody like a show-off. >> reporter: she credits her seven years starring as rachel zane on "suits" with her own style evolution, as she told "the outnet." >> everything that i used to

wear was a bit more chill and now, because of our exposure to these amazing designers, it's kind of amazing how my style has become a little more polished and adapted to that aesthetic. >> reporter: vanessa kingori, british vogue publishing director says meghan's breezy style is a breath of fresh air. >> i think a lot of people are saying, "finally," you know, she looks like me. i think it's fabulous she's of mixed heritage. people can see their daughter, themselves, their friends in her. >> what happens to a designer when meghan markle wears his or her clothing? >> it's really incredible. there's this anticipation that meghan's fashion choices will add over a billion pounds to the british economy. >> wow. >> yes. there's this wonderful story about her carrying this tote from strathberry yeah. it was sold out in 11 minutes. >> like that. >> for those small brands, it's absolutely transformative.

>> reporter: it's not just designers cashing in. wait, who is that? >> for just a second, did you think it was the real person? >> do you want to take a picture? >> emma kaler is a teenage meghan lookalike making appearances as a way to save money for college. >> when's your next gig? >> on monday, i'll be modeling the dress she's going to wear on saturday. that should be really good so, i'm hoping it's something lovely. i'm sure it will. >> reporter: in mere hours, the real meghan markle will make her biggest fashion statement yet as she steps into history. in july of 1981, it was diana who wowed the world, including abc's peter jennings. >> and here, our first glorious view of the bride. >> that was the flounciest, most over the top really, wedding dress that you could probably have. puffy sleeves. huge puffy sleeves. >> it was ruffles upon ruffles, upon ruffles with a train of ruffles.

>> reporter: 10,000 hand-embroidered mother-of-pearl sequins and a 25 foot train. >> this is magnificent. i've never seen a train like this. have you? >> i've never seen a royal wedding like this. >> reporter: those ruffles and puffy sleeves fluttered their way right into the mainstream 80s fashion. >> diana has singlehandedly rescued frills and laces from obscurity. >> reporter: now it's meghan's turn. >> at this point, every single designer in the country has been accused of working on this dress in secret. >> who's your best guess? >> the three top brands i would say. one is erdam, he's a canadian designer who lives and works in britain. >> much like meghan, who lived in canada and now is here. >> there's also discussion around christopher bailey having just retired from burberry after a great reign. >> reporter: meghan's own mom adding heat to this theory when she was spotted leaving for london with a burberry garment bag. >> and ralph and russo, also, she's worn them in the past.

>> reporter: we've seen her before in a wedding gown. she walked down the aisle in this dress for her final episode on suits. >> you're the husband i've always wanted, i can't wait to begin our adventure together. >> reporter: and at her first wedding to trevor engelson. she wore this simple sheath. >> meghan is getting married in a stunning gothic chapel. she needs to have a grand dress to match the venue. that's the most important thing. >> so while she, perhaps, might instinctively want to go for something fairly simple, she is going to have to take into consideration this incredible atmosphere, so it will be a little more elaborate than perhaps she'd like. >> it's very possible that meghan could do something like take one of diana's iconic pieces of jewelry, and turn it in to a tiara. one of kind tiaras have been made before, so that would be a beautiful thing to do. >> reporter: next, diana's legacy with the young couple lives on. >> it was one of the first things we started talking about

when we met the different things that we wanted to do in the world. >> reporter: their shared passion, the glue that brought them together.

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>> reporter: tomorrow it's official harry and meghan "husband" and "wife." but even before the vows their devotion has been on full display not just to each other, but to the causes they support. >> clearly both harry and meghan have a side of them that is about giving back, about doing good, about helping others. >> reporter: in fact it was part of that first date spark that attracted them to each other. >> it was one of the first things we started talking about when we met was just the different things that we wanted

to do in the world and how passionate we were about seeing change. i think that was that's what got date two in the books. >> plenty to talk about. >> reporter: in the nearly six months since their engagement, they've been side by side celebrating sports for disadvantaged youth, attending an anniversary service for the racially motivated murder of a black teen. visiting a café that feeds the homeless. >> they are both completely charming. it was actually pleasant. i was surprised how well informed them >> reporter: their shared passion is rooted in a powerful legacy. for harry a father whose life has been devoted to philanthropy and a mother dubbed the people's princess for her humanitarian work across the globe. >> harry is his mother's son. he can walk into a room and light it up. he's incredibly warm. busy hugging kids. we see meghan already doing that. >> reporter: diana was determined to raise her sons with a social conscience bringing them to visit homeless shelters, as seen in this photo

posted by the palace. she famously brought awareness to the plight of people with hiv and aids. >> that's something that william and i hope to carry on in her name, as much as we can, anyway. but, you know, sometimes, it, sometimes it takes something like that to, to really bring it home to people about, to what's going on out there. >> reporter: harry has found his own passions like the invictus games for wounded veterans. the site of his first public outing with meghan. and tackling the stigma of mental health. >> it is ok to suffer, but as long as you talk about it. it is not a weakness. weakness is having a problem and not recognizing it and not solving that problem. >> reporter: and he has mirrored his mother's commitments campaigning against landmines. and naming his hiv charity sentebale or "forget me not" in his mother's honor. >> i suppose it's my little way my little connection of holding onto my mother. >> reporter: meghan is also following in the example of her mother, according to andrew morton. in his new book he describes how

meghan's mother, a social worker, exposed her at an early age to those less fortunate >> her mother doria took her to mexico, to jamaica, some of the shanty towns there to give her a sense of-- that life wasn't quite as cozy and as comfortable as that in los feliz. >> reporter: and by age 11, meghan was a budding activist even confronting gender inequality in advertising. >> women are fighting greasy pots and pans with ivory clear. >> she was profiled on nick news. >> it's always mom does this and mom does that. i was furious. >> she began a letter writing campaign. >> so i was wondering if you would be able to change your commercial to people all over america. >> three months later, proctor and gamble changed the commercial. >> people are fighting greasy pots and pans with ivory clear. >> you can really make a difference for not just yourself but lots of other people. >> and once she become a

well-known actress on "suits" there were more opportunities to give back. >> even with meghan's crazy schedule as an actor, she's always made time for philanthropic endeavors. like taking her fight against gender inequality to a bigger stage the u.n. >> i am proud to be a woman and a feminist. it isn't enough to simply talk about equality. one must believe in it. >> reporter: meghan later travelled to india with world vison's lara dewar. >> she's the kind of person who always reaches out to shake a hand first. looks people in the eye, knows their name and uses it in conversation. she's a very engaging person. >> everywhere we went, meghan always has a notebook with her. she is interested in following up, and writing stories, and using her platform to really amplify the voices of the world's most vulnerable children. >> reporter: by the time meghan met harry each had a well-honed sense of purpose and duty. >> i am also incredibly grateful that the woman i am about to marry, meghan, will be joining me in this work, of which she too is hugely excited to take part in. >> reporter: in that spirit among the invitees to tomorrow's wedding celebration hundreds of people selected for their service to their communities. >> they're a global power couple. and they're really gonna be able

to make a difference to people's lives. >> reporter: next those special guests getting ready for the big day. >> it turns out we're invited to the royal wedding which is shocking really! >> it's not even sinking in. we don't know what to expect. for mild-to-moderate eczema? it can be used almost everywhere on almost everybody. the leg of this little guy? the arm of an arm wrestler? the face of a fairy? eucrisa is a prescription eczema ointment for ages 2 and up. it blocks overactive pde4 enzymes within your skin. and it's steroid-free. do not use if you are allergic to eucrisa or its ingredients. allergic reactions may occur at or near the application site. the most common side effect

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rated pg-13. >> reporter: serena williams, george clooney, sir elton john, david and victoria beckham, a few of the cast members from "suits" and most of the spice girls. what do they all have in common? they're just some of the stars expected for tomorrow's big event. >> it is a big deal to be invited to the royal wedding. >> reporter: a big deal by royal standards, tomorrow's wedding will be an intimate affair. >> he's not having an official state wedding in london. he's having a family affair in windsor. >> reporter: diana and charles hosted 3,500 guests at st. paul's cathedral. william and kate welcomed nearly 2,000 well-wishers to westminster abbey. prince harry and his bride will host just 600 friends and family inside cozy st. george's chapel, located on the sprawling grounds of windsor castle. >> it's somewhere he loved as he grew up, often visiting windsor

with his family. >> reporter: it's where prince harry was christened 33 years ago. >> granny was this. so was >> reporter: seen here in the arms of his mother at just three months old. >> we're just going to be there and say "oh hello, can we come in? we're on the list." >> reporter: they're on the list, sitting outside the chapel but just inside the castle walls -- >> they'll be able to have a birds eye view of the arrival of harry and william, and then meghan and all those little bride's maids and pageboys.

>> reporter: following protocol, the queen will be the last member of the royal family to arrive for the wedding service which starts promptly at high noon. that's 7:00am on the east coast and 4:00 a.m. on the west coast of the u.s. because the wedding is in windsor, over an hour's drive from buckingham palace. here's what you won't see, the familiar balcony gathering that other royal couple has shared. but after the i do's the couple will follow an unbroken tradition for centuries. the last time fun cousin harry made the journey, he was riding with the little ones. tomorrow, it will be prince harry's turn to present his bride. this 100-year-old horse drawn carriage will depart at 1:00 p.m. local time. people from around the world have camped out in the town of windsor for days. >> michelle from melbourne, australia. >> donna warner from new fairfield, connecticut. >> i'm faith and i've come all the way from london. >> reporter: earlier today, prince harry and brother william came out of the castle to meet the adoring crowd.

an even more exclusive party will happen after dark, thrown by prince charles at the royal's 17th century country estate, frogmore house. >> i think you're even more privileged if you make the cut to the second party, which has only got 200 people. allegedly pippa middleton has not made the cut. so you have a lot of competition going on with that invite. >> reporter: royal, celebrity, or member of the public, everyone loves a wedding. >> it's just so special and just gives you goosebumps. they're going to make a wonderful couple and wonderful ambassadors to both of our countries. ♪ it's a love story baby just say yes ♪ >> they're excited. we're all excited for tomorrow especially to see the fabulous hats and fascinate ors. david and robin, back to you. >> all right deb wearing that fascinator. >> almost as pretty as that

smile. >> we might not have have h to the exclusive after parties but we're joining you to join us here at 5:00 a.m. >> we'll have all the behind the scenes on a special the "20/20" tomorrow at 10:00 p.m. >> later on "nightline" we'll have a special report on the shooting in santa fe texas. i'm robin roberts. >> i'm david muir. thank you for all watching from all of us at "20/20." good night.