behind the scenes interviews with our actors. thanks for watching. "20/20" starts right now. so many missing moms in the news. >> now to the case of a missing father of five. >> she vanished dropping off her kids. >> this is not a woman who would ever, ever leave her children. >> and some murdered. kelsey barrett seens november 22nd. >> bup the chris watts case. >> i got a friend request on base fook. one thing led to another. we have two kids. we live in colorado and he's the best thing that has ever happened to me. >> my daddy is a hero. >> have you seen it? >> this young lady and her kids are missing right now. >> this is the very porch where he talks to the media, pleading for his wife and kid's safe return.

>> bella, celeste, if you're out there, come back. somebody has her, please bring her back. >> did he sound worried? >> no, he is didn't give a flying flip. >> i think you killed those girls. >> i love those girls. >> they were at the house when i left. they were there. >> they weren't there. they didn't leave. they vanished. >> the question now is where are they? >> it pointed to where he your daughter and your granddaughters. >> there niece way this happened to them. not them. the why? m

meet 34-year-old shanann watts. >> hey, guys. we're here from the boat today. >> reporter: a social media maven and master of the digital stage. >> i am so excited, i am thriving with you. i am confident, i am determined, and i am successful. >> she was fun, full of life. she did so many things. she had her hand in everything. she was amazing. >> love you guys. have a great day. >> reporter: just about every waking moment of shanann's life streams live over facebook. >> just enjoy your life and living it and have a blast. >> reporter: shanann's views on life -- >> i'm grateful. can you see it? >> reporter: beauty -- >> isn't it so fun to watch someone take off their make-up? >> reporter: parenting -- >> careful. >> reporter: shanann's parents, sandra and frank rzucek. she was very open on facebook. and if you were from the outside looking in, she seemed to have the perfect life. >> she did. >> reporter: did you believe that she was happy? >> absolutely. absolutely. >> chris and i are sitting here, waiting to board our flight to miami. we're going to toronto in june. have an amazing day. bye. see my hat? i love it.

>> reporter: next to shanann, that's her husband, chris, a field coordinator at a local oil company. >> i love the hat. >> reporter: shanann loves sharing their love story which started, not surprisingly, on facebook. >> i got a friend request from chris on facebook. one thing led to another, and he is the best thing that has ever happened to me. and because of my health challenges, because i got so sick, i let him in. >> reporter: shanann suffers from the debilitating disease lupus. >> you just don't sleep very good with lupus. she had her head on his lap, and they were watching tv. he didn't move. he let her sleep for four hours. i told her, "god must've sent him to you." >> reporter: what did you all think of him? >> loved him. >> reporter: less than two years later, shanann and chris are married. >> he was so in love with her. oh, my god. he did everything he could for her to make her happy. >> reporter: the couple has two little girls, 4-year-old bella and 3-year-old celeste, also

known as cece. >> say hi, cece. >> hi, daddy. >> be careful, it's hot. do you guys like my mug? oh my gosh. this is so good. the fire, the cookies. >> a lot of snow. >> reporter: how was chris as a father as far as you could see? >> he was a very loving father. as far as i knew, he loved his family. >> reporter: addy, who asked that we not use her last name, looks up to her friend, shanann. >> i just felt like she did everything the right way with so much patience. she was an amazing mom. >> she'd do anything for her children. she wanted them to have everything growing up. there's nothing she wouldn't do for those children. >> reporter: and then, last june, another baby is on the way. >> i have a doctor appointment in two hours. i know, boy, boy, chris wants a boy. i hope it's a boy for him. it will make him happy. that's just the test. >> reporter: as luck would have it, it's a boy.

>> she had a name here him already? >> nico. she had to keep it italian, you know? she was very proud to be part italian. >> reporter: cristina meacham and shanann watts have been close friends for 14 years. >> i looked at bella, and i would look at shanann and i was, like, you guys are exactly the same. with cece, she was just, joy, complete joy. >> reporter: the watts' home? frederick, colorado, a tight-knit denver suburb with a family-friendly motto. "built on what matters." for shanann and chris, family matters most. >> it was amazing just to see how they were as parents and as a couple. >> we're going to organize the basement. >> they had a great marriage. >> what happens in space?hris go he w come homerom work and take care of the girls. ♪ my daddy is a hero

>> he helped them shower and get them ready for bed. anything that he needed to. >> can you tell i'm super happy, excited? >> she was hard-driven, a hard worker. she would work 12, 14 hours a day. >> reporter: in 2016, shanann takes that strong work ethic to le-vel, a multilevel marketing company that sells vitamin infused patches. >> i'm very determined, and i am going to be extremely successful. >> reporter: she not only loved her job. she excelled at it, even winning an award from the company. >> our team is just loaded with a lot of passion, a lot of heart and i love that we're out there sharing the love with everybody. >> reporter: shanann was reaping the rewards of her hard work. >> everything is paid for, and i get to spend it with my husband. that's the best parts. >> reporter: company-sponsored trips to san diego and new orleans. >> so excited, guys. it's about to start. >> reporter: and then in august, 2018, another company trip to arizona.

this time, chris stays behind with the kids. but her friend and co-worker nicole atkinson was with her on the flight home. >> being that she was pregnant on the flight home, she was very uncomfortable on the plane, and i believe it was around 1:45 in the morning that you dropped her off? >> roughly, yeah. >> what was the last thing you said to her? >> i just told her, "if you need help in the morning, let me know." we gave each other a hug, and i watched her go in the house. >> reporter: that morning, shanann watts goes offline. >> she didn't text me, which is really odd, because she texts me every morning. >> reporter: the hunt for shanann watts. >> oh, my god. something happened. >> reporter: next. it's in here! revitalift derm intensives hyaluronic acid serum. from l'oréal. with our highest concentration of hyaluronic acid in a serum. visibly plumps skin in just one week bounce back! and reduces wrinkles for younger looking skin. powerful results. validated by dermatologists. see why there's one serum sold every minute

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>> reporter: nothing says summer in frederick, colorado, quite like the town's annual hot air balloon festival. but this past august, resident nickole atkinson has fear, not fun, on her mind. her friend shanann watts is missing. what was your first feeling in your stomach and your gut that something was wrong? >> she didn't text me. i tried calling. she didn't answer. which is really odd, because she texts me every morning. >> reporter: but on this morning, no communication from the pregnant shanann. nickole decides to try her in person.

she knows the code to the front door. what happened when you got to the house? >> i couldn't get in. they had the latch on the top like they do in hotel rooms, kind of. >> reporter: so, it was locked from the inside? >> it was locked from the inside. and then, i called chris and asked if he knew where shanann was. and he said, "she went on a play date." i said, "chris, her car's in the garage. how could she have gone on a play date when both bella and cece are in car seats?" >> reporter: nickole goes to shanann's ob/gyn, where she knows she has an appointment. but shannan is no-show. your friend, shanann, who was so excited about having this third baby -- >> she wouldn't have missed that doctor's announcement. >> reporter: you knew something was really wrong. >> my name is nickole. i'm calling because i'm concerned about a friend of mine. she's not answering the door. she's not responding to text messages, phone calls. there is no movement in the house whatsoever. >> reporter: as nickole impatiently waits for the cops, shanann's husband chris watts,

who, at work, calls her friend cassie rosenberg to see what's going on. >> he called me. i was screaming at him. i was frantic. "you need to get to the house. nikki's calling the police so they could break down the door." he said, "no. don't call the police. i don't want to get them involved." i said, "you're an idiot, and you need to get to the house because something's wrong." >> reporter: frederick police officer scott coonrod races to the watts house. >> how are you guys doing? nickole? >> yes. >> reporter: this is realtime footage can ra. >> i'll go to the back, see if i can see anything. of the perimeter, chris watts finally shows up. >> scott, how you doing? >> hi. >> so this is the only vehicle she would have? >> reporter: officer coonrod then asks to search the home. >> mind if i look around?

>> reporter: the basement, bedrooms, bathroom. the only signs of life, the barking dog. chris tells police he saw his wife early that morning before he left for work. >> the last time i talked to her was this morning. she said she was going to take the kids to a friend's house, and that's where she was going to be. and then i have texted her today, never heard anything. >> reporter: the house appears neat and orderly, nothing out of place or rummaged through. >> we all ran through the house, kind of looking for her. >> we checked upstairs, and she was not there. >> it was odd. the things that you did see. it didn't make sense to me. >> reporter: shanann's purse and wallet on the counter. wedding ring on the nightstand. and unmade beds. >> does she normally make the kids' beds? >> no. >> reporter: their beds would have definitely been made? >> yes. >> reporter: her sheets wouldn't have been stripped off the bed? >> no.

they wouldn't have. or even if they had, it wouldn't have been in the manner that they were. >> there were sheets missing from a couple of the beds. there was a sheet missing from the bed in the master bedroom. >> that wasn't on there? >> no. this wasn't on there. the master sheet, the matching sheet, the nonfitted or flat sheet, was found in the garbage can. >> reporter: eventually, they find her cell phone. >> her phone is here. >> she works from home. this is her lifeline. >> reporter: and in the kitchen. >> do your kids take any medication? >> cece takes singulair, and omeprazole. >> reporter: the biggest clue of all, medicines. including little cece's epipen. >> my daughter would never leave the house without her phone or the epipens. >> this is definitely an odd one. >> reporter: police get a break in the form of the watts' next door neighbor, nate trinaistich. he has a security camera on the front of his house. >> it's right there over your head. what i did is said, "i have the video surveillance."

the only thing i caught was chris backing his truck into his garage. >> reporter: chris comes over to your home along with the police to watch that surveillance footage. >> yes, he was standing right in my living room basically watching it. he looked very frantic. he had his hands like this in the air on his shoulders. he was really swaying back and forth. >> reporter: was he saying anything? >> no, he wasn't saying anything. he basically -- the only time i saw him show any emotion w attl >> my detective just showed up. if you want to talk to him, i'm going to get his info real quick. >> no. >> reporter: seemingly desperate to find his family, watts turns to the media for help. >> he's going to the interview,

you know, and we were just going to ask the husband, do you know where she would have went? are you afraid? are you afraid for their safety? it's one of those type of stories. >> reporter: tomas hoppough of abc's denver station kmgh is the first reporter to interview watts. >> my kids are my life. i mean, those smiles light up my life. >> his demeanor was very calm. he was very relaxed. >> i really hope that all this can lead to something positive. >> which was a little bit weird for me and my photographer. everything seemed repetitive or rehearsed. >> shanann, bella, celeste, if you're out there, just come back. if somebody has her, just please bring her back. i need to see everybody. >> reporter: so this driveway obviously played a role. the surveillance camera over here, but this was the very porch where chris watts talked to the media, pleading for his

wife and children's safe return. >> right. >> reporter: pleading for his wife and children's safe return. >> there's two things to look at here. which is verbal and nonverbal behavior. typically when we cross our arms, it means we're into a defensive mode. and we want to hold in. >> it's if they're not safe right now, that's what's tearing me apart. >> "i missed this." "i want that." so it's like the interview is all about him. >> they go into their rooms and know i wasn't going to turn their rain machines on. i wasn't going to turn their monitor on. >> did he sound worried? >> he didn't give a flying flip. i said, chris, you shouldn't do any media. i said, you're the last one to have seen them, so i don't think you should. >> and yet he did. >> i thank god he did it. i thank god in heaven that he didn't listen to me. >> reporter: who did you see on that front porch? >> not him. >> definitely somebody else. it was frightening. >> reporter: when we come back, warning signs inside the marriage.

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>> reporter: it's been more than 24 hours since shanann watts and her two young daughters, bella and celeste, vanished. >> we begin tonight with breaking news. the disappearance of a pregnant frederick woman and her two children has captured the nation's attention. >> shanann watts and her two young daughters haven't been seen in the last two days. >> they always just seemed like a normal family. >> reporter: denver correspondent clayton sandell covered the story for abc news. >> chris was actually on television dog tervieisifhad heated words before she disappeared.

>> it wasn't, like, an argument. we had an emotional conversation, but i'll leave it at that. >> reporter: so what was happening behind closed doors in the weeks before the family went missing? on facebook, shanann was ecstatic about the summer. >> i feel really blessed this summer. six weeks, we are going to be in north carolina, right? we're going to have a little -- a lot of fun. >> she was very excited to be going to north carolina, seeing her family. the children loved the grandparents so much. >> reporter: you were with them for six weeks? >> six weeks. we went to the beach. >> we played in puddles. >> you played in the rain and got all wet. >> mm-hmm. >> we went to the zoo. goodness. >> we had a lot of fun. >> reporter: chris stays home in colorado working. but even from across the country, shanann senses a change in her husband. how did your daughter describe it? did she say it happened suddenly? >> a few weeks, maybe a month. just cold as ice, and not responding and replying. >> reporter: text messages between chris and shanann show their marriage unraveling.

while you are working and living the bachelor life, i'm carrying our third. and fighting with our two kids daily. it's not hard texting love you and miss you. >> she was looking forward to him getting there. >> reporter: did you ever at any point feel like anything was going on in their marriage? >> she just couldn't understand why he was so cold. >> reporter: something had changed. >> yes. nothing that was really -- that i could physically see. >> i don't know how you fell out of love with me in 5 1/2 weeks. i left you, you couldn't take your hands off me. you show up and i have to practically ask for a kiss in the airport. >> reporter: a few minutes later, she adds -- >> if you are done, don't love me, don't want to work this out, not happy anymore and only staying because of kids, i need you to tell me. >> i'm not staying because of the kids. they are my life, and that will not change. i'm not sure what's in my head. >> reporter: what had she told you? >> she just told me that chris said he wasn't happy anymore and she didn't know what was wrong.

>> reporter: and once they are back home, the relationship appears to be going from bad to worse. shanann texts her friend. >> chris told me last night he's scared to death about this third baby. and he's happy with just bella and celeste and doesn't want another baby. he has changed. i don't know who he is. >> reporter: with her crumbling marriage in mind, shanann goes on that business trip to arizona, leaving chris with the girls and her bubbly self behind. >> she wasn't herself. she was trying really hard, but her mind and her heart were really with what was happening in her marriage. >> i sometimes can be bitchy and he gets that side of me. i know i tend to make him feel like he can't because i have control issues. >> she was trying to fix it. she was very much analyzing everything she said or did. >> reporter: did she ever suspect another woman? >> i think she did entertain the idea. because she did get -- i don't know if she checked the bank

account or if she got the alert on her phone. >> reporter: an alert to a credit card charge from the lazy dog sports bar that certainly looked fishy. a $62 salmon dinner that's literally not adding up. >> she realizes, or believes, that that's too much money for just one person and suspects that chris is having dinner with somebody else. >> reporter: and her suspicions are right. that somebody is a young, pretty brunette named nichol kessinger. this is audio from an interview she would later give police. >> we got along really well. i thought what we had, it was very comfortable for me. i enjoyed it. i think he did very much as well. >> kessinger is a co-worker in chris' office. and he tells nichol that he is separated and that they are working on getting a divorce. >> reporter: these are photos released by authorities of their time together. >> he didn't have a wedding ring on his finger. he didn't even mention his kids right away either. and then one day he told me that he had two kids. i thought it was kind of cute. i was like, "oh, he's a dad." >> the relationship between chris and his

co-worker/mistress heats up pretty quickly. kessinger describes it as being very passionate, that they were having sex three, four times a day in the beginning. >> reporter: chris appears to be falling hard for nichol, searching on google, "when to say i love you for the first time in a new relationship." >> so, did he ever tell you that he loved you? >> yes, he did. >> did you ever tell him the same? >> a couple times. >> by all accounts and by all descriptions, it sounds like they were beginning a dating and intimate relationship. >> reporter: a blossoming romance with love letters and all. >> have you read those love notes that chris watts was writing nichol kessinger? something like, "you turn me on. you make me melt, and then you cool me off like rain." really? >> they had gone to a mustang car museum. they had gone camping and hiking in the sand dunes. >> reporter: all those videos and photos, including nude pictures of nichol, would end up in a secret app camouflaged as a

calculator on chris's phone. >> my daughter had no clue. she was clueless. >> reporter: back in arizona, a storm delays shanann's flight home. at dinner, she confides in her closest friends. >> she was definitely wanting her friends to be able to give her some advice, support. >> reporter: her friends don't know it then, but the very next day, shanann would vanish. and when word of her disappearance hits the news -- >> tonight police issued a missing endangered alert for shanann watts and her two daughters. >> reporter: -- nichol kessinger learns chris' wife is not only missing, but she's 15 weeks pregnant, and decides to go to the police. >> i just realized that he was lying to me, and i was like, "well, if you can lie to me about this, what else are you lying to me about?" >> reporter: that's exactly what police want to know. in another interrogation room, chris watts makes a rather unusual request, asking for his father instead of an attorney. >> can i talk to my dad or something? >> reporter: what he reveals with the cameras rolling, next. (meg vo) i can see if my endometriosis pain gets better...

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>> reporter: the vast, open fields surrounding frederick, colorado, have become ground zero in an all-out search for mother shanann watts and her daughters, bella and cece. >> this became a massive law enforcement effort to find shanann and the two girls. it was all hands on-deck. the fbi, the colorado bureau of investigations had joined the frederick police department. >> have you seen this lady? >> this young lady and her kids are missing right now. >> we have a whole team of people working on this. >> they were setting up roadblocks that anyone coming in and out of the area if they had someone anything, asking if they had heard or seen anything suspicious that might lead them to shanann and the girls. >> how are you doing? we're handing out flyers regarding a missing woman in the neighborhood. have you heard about her? >> no. >> okay. >> reporter: with chris watts'

permission, authorities bring out k-9 units to track a scent. but over in north carolina, shanann's parents smell a rat. you immediately suspected chris? >> yes. i told the police to find his gps. because his gps is going to tel. >> reporter: the gps from chris watts' work truck showed he left his house at 5:46 a.m. and arrived at the cervi 319 oil well 47 minutes later, exactly what he had told police. >> go ahead and have a seat here, chris. >> reporter: saying he has nothing to hide. >> it's not on or anything right now. it's not going to -- >> reporter: watts agrees to a polygraph exam. >> did you physically cause shannan's disappearance? >> no. >> are you lying about the last time you saw shannan? >> no. >> do you know where shanann is now? >> no. >> the polygraph shows that he's being deceitful, that he's not telling the truth. >> it is completely clear that you were not honest during the testing. and i think you already know that.

you did not pass the polygraph. >> i didn't lie to you on that polygraph. i promise. >> we need to talk about what actually happened. >> reporter: investigators press watts. >> is there a reason you feel sick to your stomach? i can tell on your face. i could tell that you are worried to just come clean and just be done with this. >> i'm not proud of it. didn't think i could ever do it. but i did. >> reporter: he doesn't admit to a crime. instead chris watts confesses to an affair. >> i cheated on her. and i feel horrible for it. she was pregnant. >> reporter: but he refuses to name his mistress. >> who is her? >> i don't want to get her involved and ruin her life. she is a wonderful person. i saw her. she took my breath away. and i never thought in a million years something like this could happen. i've never felt like this about anyone in my lifetime. >> struck me as very odd, because investigators even said,

can we stop talking about the other woman and get back to trying to figure out where your wife and two daughters are. >> leave her out of it. and get back to your wife and two daughters. where are they? >> they were at the house when i left. they were there. >> they weren't there. they didn't leave. they vanished. the only way they could have left is in your truck. >> reporter: the agents seem be getting nowhere. so they switch strategies. >> did shanann do something? >> she didn't do anything to these kids. we both love them with all our hearts. there's no way. >> could have been an accident. something happened in the house that you know about. >> the key here is to find some lever in chris that will get him to tell the truth. whether it's saving face, whether it's to minimize what he in reality has done, but also to maybe blame other people.

>> i want to know. did something happen to these baby girls first that you had to take into your own hands? and deal with? >> that you had to clean up for shanann? >> chris, you have to tell us. something happened to these baby girls. >> reporter: eventually, watts asks to speak with his father ronnie watts, who has just flown in from north carolina. police oblige, an unusual move, allowing a third party into the interrogation room. >> both of them? >> yeah. >> she choked both of them to death? >> i freaked out and did the same thing to her. >> oh, my god. so, if she killed bella and cece, choked them to death, you lost it and choked her, or what? >> mm-hmm. that's rage. >> oh, son. >> reporter: it's a stunning statement. chris watts claims shanann had attacked the kids. and he killed her in a fit of rage. cbi agents re-enter the room.

>> i saw the monitor. bella's covers were pulled off. and she was laying there. so i went over to cece's. and she was in there with her on top of her, choking her. i freaked out. i ran in there and got on top of her. >> what did you do? >> i did the same thing to her. >> who, shanann? >> yes. i'm not that person. >> he speaks quietly. he's not very animated. he's just kind of laying it out, matter of factly. >> was it a choke like this? or, like, a headlock. >> a choke. >> you killed her with one hand or two hands? >> i was coming from the back. i couldn't really tell. >> he never attempted resuscitation, never checked on them, never called 911, never asked for assistance. according to him, he knew that they were already dead by their appearance. >> i think that you killed these girls before their mom came home.

it just doesn't make sense. if i walked in and a kid was decapitated, i would call an ambulance. i think we're very close to the truth but not quite there yet. >> i'm not that monster. i didn't kill my babies. >> he blames her for the murders of her two little girls, that would never happen. he lied to take the blame off himself. >> reporter: authorities aren't buying chris watts' story either and arrest him for the murder of his pregnant wife, shanann watts and his two daughters, 4-year-old bella and 3-year-old cece. how do you reconcile the chris you loved with the one who's being arrested? >> the devil comes to you in any shape, size, and form, and can be transformed into anything. >> reporter: did he snap? >> he must have snapped. because there's nothing else i could figure out, what happened to him. >> reporter: next, police have a suspect in custody. but they need to know what he did with the bodies. >> where did you put them after? >> reporter: when "20/20"

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>> reporter: in a dramatic turn of events, chris watts is in jail. when you learned that chris was 100% involved, how did you react? >> to be honest with you, i kind of went numb. i sat in my bed and watched the news, and i couldn't move, and i couldn't breathe. >> once chris watts admits that his wife and his daughters are dead, the question now is, where are they? >> reporter: back inside that interrogation room, chris reveals the heartbreaking details of how he disposed of his family's bodies. >> are they buried in something, or -- >> shanann is.

>> the babies? >> that's what i feel horrible about. they're in a freaking oil tank. i didn't know what else to do. >> reporter: he's asked to point in a photo the exact location. >> whereabouts are shanann and the girls? can you mark it for me? is that "s" for shanann? okay. and where are the girls? >> here and here. >> reporter: watts marks the spots with their initials. r pregnant m sow graveate oil the missing bedsheet, also found on the scene. where he pointed to, where he put your daughter and your granddaughters. >> sickening, isn't it? >> reporter: how do you react to that? >> devastated, you know. >> he is a monster.

how do you put someone you love into an oil tank? >> especially your children. >> this had to be one of the most grim scenes any investigator could come across. at some point, chris has to take the bodies of his 3-year-old and 4-year-old daughters. and he's got to basically stuff them into these tanks. >> reporter: chris' mistress breaks down thinking about that he did to his daughters. >> he's so disgusting. i am so ashamed of him and everything. and i just -- oh, those little girls. they're so little. they're so little. why? why, why, how? i don't even understand how you

could bring yourself to do that to somebody who's, like, that big. >> reporter: the little girls' autopsies are key to the district attorney's case. >> they weren't strangled. those girls were smothered. his statement that he had seen shanann strangle those girls all of a sudden became an enormous lie. >> this kid keeps me going. >> i knew in my heart of hearts, the friend that i cared so much for would never hurt her babies. i knew from day one that that was not true. >> bella has her baby. >> bella, the 4-year-old, she had tried to struggle back against her father as he smothered her. >> to find out that my granddaughter struggled to live, that probably threw us over the edge. ♪ amazing grace >> reporter: people i know came

from all across this country to where your daughter and chris lived to pay respects, to light candles, to leave stuffed animals. that had an impact on you. >> oh, yeah. >> yeah, it did. >> let them know that there will be a day when they'll hold those babies again, that they will see shanann's beautiful smile. >> we did scream at god. yes, we did. >> reporter: why? >> that's the big word, "why." >> there appeared to be some serious financial trouble in the watts' home. they were months behind on their mortgage. they had thousands of dollars in debt. >> the motive that we know of is wholly unsatisfactory. the result in this case, because of some newfound love coupled with the occasional financial issues that arise in many households, just didn't make any sense. >> mommy has a baby in her belly. >> yay!

>> when you look at pregnant women that are killed, right behind automobile accidents is homicide. the reason people like chris don't get a divorce is that they want to get out from under the financial hardship of soon-to-be three kids and a wife. what's interesting about him is he comes across as a rather passive, introverted person, but you really have to be this narcissistic, anti-social person that's full of anger and rage to commit this kind of crime. >> next to the headline, a father and husband offering a plea deal to save his life. >> reporter: chris watts agrees to plead guilty to killing his pregnant wife and young daughters in exchange for no death penalty. >> first degree murder, disposing of a body and the unlawful termination of a pregnancy. he took responsibility for all of it. >> reporter: next, sentencing day. shanann's family comes face to face with chris in court. >> you heartless monster.

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>> reporter: as this small community in mourning comes to grips with the depths of its loss -- >> it's too close to home. it's heartbreaking. >> reporter: -- shanann watts' family celebrates the lives of their loved ones in a funeral that not surprisingly, streams live over the internet. >> it gave everybody a chance kind of virtually to be there, pay their respects, mourn together. >> reporter: just three months after murdering his pregnant wife and two young daughters, it is judgment day for chris watts. watts must listen to victims' impact statements. >> you carried them out like trash. you buried my daughter shanann in a shallow grave, and then you put bella and celeste in huge containers of crude oil. this is hard to say, but may god

have mercy on your soul. >> reporter: shanann's mother, sandra. >> we loved you like a son. we trusted you. i didn't want death for you because that's not my right. your life is between you and god now, and i pray that he has mercy for you. >> reporter: watts' mother cindy speaks directly to her son. >> our families have been irreparably broken by the needless deaths of shanann, bella, cece, and nico. this is something we will never get over. now, to my son, christopher, i have loved you from the beginning. and we still love you now. >> reporter: it is when sidney turns to look into her son's empty eyes that he finally breaks down. >> we will remain faithful as

we love you. we forgive you, son. >> reporter: through his attorney, watts issues a short apology. >> mr. watts has asked us to share this morning that he is devastated by all of this. and although he understands that words are hollow at this point, he is sincerely sorry for all of this. >> reporter: chris watts is sentenced to life in prison without the possibility of parole. he dribs how he drives their bodies to the oil field. >> and the girls right? >> cece was first. >> wrus wr exactly was shiwen it happen snnchth it was blanket over her head. >> once she's gone, did you pull her out? >> i pulled her out. >> she went into the tank, and bella is still in the back of the truck alive? >> yes. she asked the same thing is going to happen to cece. and she said, no daddy.

that east the last thing she said. >> ohio do you want your daughter to be remembered in the world to remember her and your granddaughters. >> bella wanted lipstick on like momy today. >> she wanted to soar the earth and she said i want to leave my mark on the earth and she did. >> reporter: sandra's unshakable faith gives her the strength to keep alive the happy memories of shanann and her beloved granddaughters. >> oh, my goodness. come give me hugs. oh! i love you. >> how horrific it just have been to listen to that confession. >> it's really unimaginable. one of the worst stories we ever

had to share here. thankfully they have videos to hang on to. that is "20/20" tonight. i'm david muir. >> and i'm amy robach. good night. >>

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