[ cheers and applause ] this is "nightline." >> tonight, american heroes. those three brave young men who took down this suspected terrorist on a train. they have now been given france's highest honor. and now we're hearing about a fourth american hero on the train. and those chilling tales of survival. >> i thought to mymyself -- viral. >> no, you didn't. >> i did. >> turning this couple into overnight internet celebrities. now a miscarriage and a scandal. >> i sought forgiveness to god. he has forgiven me. >> have turned sympathy into skepticism among millions of viewers with critics crying tmi. are these parents taking oversharing way too far.

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seconds. good evening. tonight we are going to take you inside the story of three young american who just today received france's highest honor. these young men fought, tackled

and hogtied a heavily armed gunman on a crowded train. now we are learning about another american, a college professor who also leapt into action. today, abc's david wright retraced the journey of that fateful train. tonight two of the american heroes arrived in germany to visit a military hospital. first stop on their journey home after this incredible ordeal. they are the toast of france. celebrated today for their valor and their humanity. after wrestling a gunman to the ground on a moving train. but that incident serves as a grim reminder of the dangers of modern life as one of the men who shared the legion of honor today, chris norman put it. >> one way or another we are going to be facing this kind of problem quite a few times in the future. and you know i would invite you all to think about what do i do in the situation?

>> reporter: we retraced the journey borning talis, 9364. three americans on vacation. childhood friend from sacramento. airman first-class, spencer stone. army national guard specialist, alek skarlatos and anthony sadler. they happened to be in carriage 12, bah the wi-fi was bad in the car before. the three were traveling on the high-speed train bound for paris friday evening. half asleep when they suddenly heard a gunshot. most of the passengers in carriage number 12, that noise was the first sign they were in harm's way. the gunshot came from the far end of the carriage. the gunman emerged from the bathroom here shirtless and strapped with an ak-47. christina had the reaction most would have. >> when high had the gunshot. i immediately dove under my seat. and i had already had the tray table down. i lifted it up, a bit to get under my seat. then i pulled it back down so

that i had something else over my head beside my hands. which i was, literally kind of doing this. >> reporter: before you judge her, know tat she is just 4'11" and at age 29 was on her very first trip overseas. >> i literally saw my life flash before my eyes. the moment that the gunshots occur, and i saw a man bloody, like fall to the floor, i thought to myself. i may die today. very real thought. and for some reason that's why i was texting my friend, i thought, like, somebody has to know what's going on with me in case, in case that happens. >> reporter: she sent photos of the action as it unfolded. a blood spattered duffel bag. a passenger down. another american, a college professor named mark moogalian, the first to confront the gunman. moogalian managed to grab the ak-47 which jammed. he turned to protect his wife.

not realizing the gun man also had a luger pistol. moogalian shot in the back, bullet piercing his lung and neck. when the three friend sprang into action. >> alek hit me on the shoulder and said, let's go. ran down. tackled him. we hit the ground. alek came up. grabbed the gun out of his hand. while i put him in a chokehold. >> a british passenger. jumped to help stone hold him down. >> seemed like he pulled weapons left and right. pulled out a handgun. took that. took out a box cutter. started jabbing at me with that. >> reporter: airman stone almost lost his thumb to the box cutter. the gunman stabbing himmen the neck too. >> it all happened quickly. almost immediately when i went under what i had seen was a man bleeding profusely on his neck as if, i assumed he was shotten the neck since i heard a gunshot. and he had this duffel bag in his hand that he dropped in the seat adjacent to me.

>> reporter: the gunman was face down on the floor. unconscious and hogtied with the conductor's redneck time. his arsenal of weapons on the seat beside him. >> spencer, i gather after you were injured, you rendered first aid to one of the passengers injured. can you tell me what you were able to do for him? >> i just went over. saw that he was skirting blood out of the left or right side of his neck. and i was going to use my shirt at first. but i realize that wouldn't have worked. so i just stuck two of my fingers in his, the hole, found what i thought to be the artery, pushed down the bleeding stopped. >> reporter: his quick actions may well have saved mark moogalian's life. >> well i feel our training mostly kicked in after the assailant was subdued frankly. when i cam to medical care and things like that. >> reporter: french authorities identified the gunman using a dna swab as 25-year-old, ayoub al khazzani, born in morocco. france had him on a security

watch list as of february 2014. after spanish authorities told them he had ties to islamic extremists. officials believe he may have traveled to syria this year hoping to become a foreign fighter there. al khazzani is held without charge under france's equivalent of the patriot act. a lawyer who met with him insists he isn't a terrorist. she claims he found the gun in a brussels park and planned only to rob the train and shoot his way out through a window. >> the guy had a lot of ammo. his intentions were pretty clear. >> it doesn't take eight magazines to rb s tos to rob a train. >> reporter: today at the french equivalent of the white house, a special ceremony. there they are arriving. a state occasion. the french president greeting them on the stair. awarding legion of honor. france's highest medal. the three americans wore polo shirts, clearly on their

european vacation. they dent pack for a medal ceremony. the french president said their courage and valor are an example to the world. >> me, personally, i am waiting to wake up. this all seems look a movie scene or something. >> it feels pretty crazy. and i never thought i would be here in this position. so it's -- it's unreal. >> i would say thank you so much. i would give them, i would shake their hand. i would give them a big hug. you know? and tell them that they are heroes. even if they've don't think they're heroes. i think that they're heroes. i think obviously they received the highest honor in france this morning. and they deserve that. >> reporter: a sentiment echoed around the world today. and an honor they will share with injured passenger mark moogalian, as soon as he recovers from his wound. i'm david wright for "nightline" in paris. up next, many of us share

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call 1-800-341-9716. speaking as a new parent. it's hard to resist the urge to share pictures of your kids on social media. this is my son alexander, cutest baby on earth. i can say that objectively. when do you cross the line of sharing and oversharing? the question facing the parents you are about to meet. here is abc's aditi roy. >> reporter: you are watching a husband with a plan. samuel rader its about to discover if his wife is pregnant. >> brought home a pregnancy test. this time around i am going to be doing the announcement. i hope. i hope so bad she is pregnant. >> reporter: texas couple. sam and nia rader, found themselves in a firestorm of controversy after posting this video. it started out innocently enough.

using a dropper, he extracts a urine sample from the toilet and minutes later. >> oh, my gosh. oh, my gosh. armed with a positive result, he surprises his wife with the news. >> what did you do? did you get a dropper out of the toilet? no you didn't. >> i did. >> no way. are you serious right now. no way! are you serious? >> dead serious. >> reporter: the video quickly went viral. skyrocketing to more than 14 million views in just two weeks. >> she wrote me and work ad and said i am two weeks late. i was like i have to got on this. take some pregnancy tests. that morning. came hope. the rest is in the video. >> so i'm pregnant. >> yeah. >> your's pregnant. >> i'm going to have a baby. >> what made you think of the yesterday to test the toilet watter? >> she has been doing this since we've been married. doesn't flush at night.

as gresoss as that sound. how else would i get urine without her knowing it? >> reporter: it may sound extreme. but they are part of a growing group of families who are sharing every moment of their lives on youtube. and making lots of money. >> it's been amazing. just so much fun. especially like looking back on the videos. we are getting to see our kids grow up. >> reporter: from birthing videos. >> oh! >> reporter: to babies at the water park. >> yea! >> reporter: and even doctor's appointments. >> ooh, ooh, ooh. bless you. >> family blogging is a huge new trend. we see a lot more people getting in on this. not something in their spare time. if the's becoming a career. putting of videos every day. amassing hundreds of thousand of followers. that does lead to a career for a lot of these people. >> reporter: in the quest for clicks some say the parents are taking it too far. overexposing their children and

oversharing even in times of crisis. >> we were so happy. >> a few days after the viral online pregnancy announcement. >> you are so funny. >> nia says she suffered a miscarriage. >> the hardest part knowing it is gone. >> once i miscarried that was difficult for me. do i tell them? it would have been obvious on our channel if we stopped talking. and my belly never grew. because well blog every day. we had to fill them in on that. >> reporter: it was this tweet that turned sympathy into skepticism. our tiny baby brought 10 million views to her video. and 100,000 new people into our lives. she turned our life around and brought us closer together. the couple was slammed online for touting their bump and followers post miscarriage. some viewers questioning if the pregnancy was ever real in the first place. some skeptics say it was a ploy to get more followers. that-up staged the whole thing? how do you respond to that?

>> well our simple response is we absolutely didn't stage it. we are christians. the last thickng we would do is deceive our audience. a lot of people thought as if we were gaining from ore babyur baby's death. that wasn't it. i was trying to make it clear we gained so much from the life of our baby. >> reporter: with the success of their vlog, sam quit his job as a nurse to pursue the youtube channel full time. >> the goal its to shine the light of god and get the message of christ to the world. our main goal as a youtube family and to show what a family looks like when god is in the home. >> reporter: on friday, the christian couple was thrust into the spotlight once again. sam was outed as having been a member of ashley madison. the dating website known for matching up married cheaters. >> life is short, have an affair. >> sam and nia declined to comment for our cameras, but took to youtube. >> i made the account two years ago.

our past. youtube. the account was open out of pure fleshly desires and just simple curiosity. i sought forgiveness to god heave has forehe has forgiven me. to face from the website. i never had an affair with anybody ever, while i have been married with nia. >> this issen our past. it is unfortunate it is being dug up right now. but you know our marriage is worth fight for. it always will be. >> the ashley madison scandal has tarnished their image. people are calling them liars. actors. fakes. even questioning whether or not they are real christians. controversy seems to follow this infamous couple. this past weekend after packing their bags and heading to a vloger conference, sam was reportedly thrown out after fighting with a fellow vloger who he says ridiculed his family on twitter.

>> what have you got there, babe? >> for now, sam and nia have no regrets and plan to keep sharing their lives online. >> we'll do the same thing all over again, if we, if we are lucky enough to have another baby. life has ups and downs. we shoef thew the ups and downs. and try to stay as real as possible. sure. >> reporter: when your kids are all grown up, when they look back on this, what do you want them to get from this whole experience? >> that we loved them so much. awe thought we love them every single day. they made our lives beautiful. and i just think they're going to love it. i would love to look back on my life as a kid. even if we quit a couple years down the road and do something else. looking back on their early years, i think that would be amazing. >> reporter: do you think they will be embarrassed of anything? >> yeah, i'm sure. >> do you want to give her a bubble bath? >> yeah. >> want to take one with her? >> you will look back on some. what was i thinking? why was i saying that?

>> for "nightline," aditi roy, terrell, texas. >> up next on "nightline" -- the story behind why the ceo of apple went to a small classroom in alabama with our robin roberts. hey terry stop! they have a special! so, what did you guys think of the test drive? i love the jetta. but what about a deal? terry, stop! it's quite alright... you know what? we want to make a deal with you. we're twins, so could you give us two for the price of one? come on, give us a deal. look at how old i am. do you come here often? he works here, terry! you work here, right? yes... ok let's get to the point. we're going to take the deal. get a $1000 volkswagen reward card on select 2015 jetta models. or lease a 2015 jetta s for $139 a month after a $1000 volkswagen bonus. (wolves howling) when heartburn comes creeping up on you. fight back with relief so smooth and fast. tums smoothies starts dissolving the instant it touches your tongue. and neutralizes stomach acid at the source.

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thirst for the extraordinary. ahhh perrier! hey terry stop! they have a special! so, what did you guys think of the test drive? i love the jetta. but what about a deal?

terry, stop! it's quite alright... you know what? we want to make a deal with you. we're twins, so could you give us two for the price of one? come on, give us a deal. look at how old i am. do you come here often? he works here, terry! you work here, right? yes... ok let's get to the point. we're going to take the deal. get a $1000 volkswagen reward card on select 2015 jetta models. or lease a 2015 jetta s for $139 a month after a $1000 volkswagen bonus. finally tonight, what is the ceo doing in a tiny elementary school classroom in alabama. here's "good morning america" anchor robin roberts. >> for the first time in history. >> reporter: while the sixth

graders in mr. moore's class are learning american reconstruction by producing a news show. apple ceo tim cook is focusing on an academic revolution. >> understanding because of winn-dixie. >> reporter: this school is 114 schools in 21 states starting the year with brand new technology. that many kids have never experienced before. >> i think technology has to be a key part. so, that's why we are here. i wouldn't be where i am today without a great public education. too many times today kids aren't given the right for a great public education. and this isn't right. it's not fair. >> though young people that we just saw in that classroom will now have better access through those ipads. >> kids are born in a digital world. too many kids when it comes time for the 8:00 bell to ring, go to an analog world. it's not engaging.

it's boring.