join in on the conversation on facebook and twitter. "20/20" starts right now. tonight, on "20/20, "-- the week of a historic deadly heat wave. >> the heat wave has lasted for days. >> all over the country. >> dangerous heat that's coast to coast. >> millions swelter as 44 states average 90 degrees or higher under a glaring summer sun. tonight we take you inside one of the most notorious cases inside a baking hot car proved deadly. >> cooper harris, not yet 2 years old. >> i kissed cooper od-bye, not knowing that i was literally kissing him good-bye. >> in a trial that h families a >> he dlestroyed my life. >> and a baby left inside a hot

car. >> what of i done? >> that hot car trial in georgia. >> pounded by press for two years. >> we have no comment. >> the boy's mother in her only network tv interview, telling "20/20" about a life turned upside down. >> within weeks of your son's death, another bombshell that your husband, ross, was leading a double life. >> standing by her ex-husband in court. >> he must have forgot. >> even after discovering the worst possible secrets about him. >> ross was messaging 30 people, mostly women, about sex the day cooper died. decide was little cooper's death a tragic accident or a terrible, deliberate crime? >> this is anybody's story who has been betrayed by their spouse. >> good evening. i'm amy robach.

david muir is off tonight. a mother speaking through unimaginable pain. what happened to her baby boy, and why? this is your for virs intvery f interview. >> right. >> it has been 2 1/2 years of heartbreaking silence. not being able to speak out for myself, not being able to speak out for my son, and it's time for me to do it's time for me to talk about him. it's time for me to defend his legacy. >> reporter: you want to change the narrative. >> exactly. >> reporter: it's a narrative that begins here, 32 years ago deep in the bible belt in the small, rural city of demopolis, alabama, a hardscrabble southern river town where a long day's work fishing is met with a relaxing night on the front porch. >> i was raised primarily by a single mother. and i think that the strength the you acquire from watching your mother raise you by herself, it changes you, but in a good way.

>> reporter: leanna says she grew up introverted, but earnest. >> i'm sure the people that went to high school with me would probably categorize me as the goody two-shoes. >> reporter: she flirts with the idea of becoming a nurse, but what matters most to leanna, she says, is becoming a mother. >> i knew that i wanted to get married. and i knew that i wanted to have children. >> reporter: you wanted to be a wife and a mother. >> yeah. >> reporter: at just 20 years old, part of that dream comes true when leanna meets 23-year-old ross harris, a local 911 dispatcher, who will become a guitarist in their local church. who was ross when you met him? >> the exact opposite. outgoing, extrovert, he would talk to anybody. i think we were able to bring out each other's best parts of our personalities. >> reporter: leanna says ross brin while she helps him focus on the future, inspiring him to go back to school for a business degree. you made him want to be a better man. >> i thought so. >> reporter: how quickly did you fall in love with ross? >> it was pretty fast.

i would say within a month we were talking about getting married. >> reporter: but friends and family are worried things between the young couple are moving a little too fast. >> i knew that there were people that i was very close to in my life that were taken off-guard by the relationship because it we were talking about marriage so quickly. >> reporter: what did you say to them when they said, "why are you rushing this?" >> "i know what i'm doing." that was kind of the attitude. >> reporter: their courtship was quick but it would take longer to start that family. when they finally decide to start trying it's one disappointment after another. >> every month was a roller coaster. i would take a pregnancy test every month and bawl my eyes out because it was negative. >> reporter: by now, they've moved to an atlanta suburb where ross is working as a web developer for home depot, leanna as a dietician. then, finally, that roller coaster ride reaches its peak. leanna is pregnant. >> we just kind of sat on the bed, like, "we're going to be parents. i'm going to be a mom. you're going to be a dad. this is crazy." >> reporter: they welcome their

son cooper mills harris on august 2, 2012. describe that moment when you first held cooper. >> it's hard to describe that moment. it's the best feeling in the world. this little person comes into your life and changes everything. >> reporter: but like so many babies, cooper is fussy and those early months are a blur of sleepless nights. how was ross in terms of being a father and helping you through those really, really tough first few months? >> he was more involved than i ever anticipated him to be. he would get up and try to put him back to sleep. he did everything that i did and never complained other than the normal complaints of new parents, "i'm so tired." >> reporter: as cooper approaches his second birthday he was hit milestones and developing quite the little personality. >> he was full of life. adventurous, definitely.

we got quite the number of phone calls from daycare. "cooper is climbing on the table. and fell over and bumped his head." he was just happy all the time. ♪ if you're happy and you know it, shout hurray ♪ >> i think that he had ross's personality. >> reporter: leanna says father and son also share a special bond. cooper loved his daddy? >> absolutely. >> reporter: what would he do when ross walked in the room? >> when he saw ross, it was just, like, he just lit up. >> reporter: that loving relationship is just one reason that all that happens next, seems so unbelievable to leanna. june 18, 2014, the day that would forever change your life. it was a day like so many others. ross was in charge of dropping cooper off at day care in the morning, and leanna would plan toim upe afternoon. it was typical in one other way.

it's a june afternoon in atlanta. temperature, 91 degrees. >> i left work probably around 4:00. i had about an hour drive. i got to the day care. and walked in just like i would any other day. >> reporter: security cameras capture leanna from the moment she arrives. >> the day care teacher that was there, she said, "what are you doing here?" and i said, "i'm here to get cooper." and she just kind of looked at me. she said, "well, cooper's not here." and i thought she was joking. "no, really, where's cooper?" and she -- she just -- she looked me dead in the face and got my attention. she was like, "he's not here." >> reporter: what did you think? >> i didn't know what to think. it didn't make any sense. >> reporter: were you scared? >> absolutely. immediately. >> reporter: what were the thoughts? >> did somebody take him from day care? i think that was the first thought i had. and then the thought crossed my mind, "ross must have left him in the car." >> reporter: and you said that out loud? >> i said that out loud. yes. >> reporter: why did your mind go there? >> nothing else that my mind was going to made sense.

>> reporter: one of the daycare workers accompanies a panicked leanna to ross' office building. >> rode through the parking lot. did not see his car. the next place my brain went was, "well, maybe ross left him at home. like, maybe he just forgot to take him to day care." >> reporter: was ross a forgetful person? >> yes, he could be a forgetful person. >> reporter: it's now 5:09 p.m. a breathless leanna can't find her husband. can't reach him on the phone and can't understand where her young son could be. then, in the lobby of ross' office, leanna notices everyone fixated on the 5:00 news. >> i noticed that the guy that rode over with me and the security guard were watching something on the tv. it was odd to me that they were so intent on it. >> reporter: leanna's phone finally rings, but its not her husband. >> i answered the phone, and there was a detective on the other end. and he wanted to know where i was, and i told him. and he said, "well, you need to stay there. we're going to come to you."

and i said, "it's bad, right?" and he said, "yes, it's bad." >> reporter: as she waits for the police, she begs that day care worker to tell her what was going on. >> he said, "all i know is what we saw on the news. we saw ross's car on the news, and they said a child had died." >> a child had been in the back of a very hot car. >> i think that that was the point that i started to shut down. >> reporter: you went blank? >> i went numb. >> reporter: 5:51 p.m. the detectives arrive. their conversation, recorded as they deliver the worst news any parent can get. >> there's no easy way to tell you this. your child is deceased. i'm very sorry to have to tell you that. >> reporter: coming up -- >> oh, my god. >> reporter: a father's anguish is on full display. so what is it about ross that immediately makes police think the worst? >> it's almost like he's putting on an act. that's how some of the witnesses described it. >> my boy! >> reporter: when "20/20"

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>> reporter: ever since little 22-month-old cooper harris lost his life, his mother leanna has been replaying the events of that fateful hot summer day in her head, minute by minute. it begins with a mad dash getting ready for work. do you remember your last moment with cooper that day? >> i'm not a morning person. and, of course, as usual, i didn't wake up when i wanted to or needed to. i was getting ready to walk out the door, and i came back and, you know, i told them both "bye" and i kissed cooper. i kissed cooper good-bye. not knowing that i was literally kissing him good-bye.

>> reporter: 8:30 a.m. ross loads cooper into their small suv. first, a quick stop for breakfast at this chick-fil-a. here, surveillance video from that morning shows ross holding cooper while they order food. on any other day, ross would leave the restaurant and turn left at this intersection to drop cooper off at daycare. but on this hot summer day, ross drives straight at the intersection, towards his office, where he parks and, 30 seconds later, exits the car. see here as he walks across the parking lot, swipes into his building and leaves little cooper behind. more than six hours later, ross leaves work at 4:15 p.m. here he is swiping out of his building, casually crossing the parking lot. he gets in the car, seemingly unaware of his son mere inches

from him in the back seat. he drives roughly a mile and a half before he pulls over and calls out frantically to onlookers. >> tell me exactly what happened. >> the guy pulled in a parking lot, and the baby's not breathing, it doesn't look like. >> reporter: at 4:24 p.m. police rush to the strip mall parking lot where the former 911 dispatcher is in the throes of his own emergency. >> he kept saying, "what have i done?" laid him on the ground, starting doing cpr, trying to resuscitate him. apparently the child wasn't responding. >> reporter: despite ross' apparent initial distress, the cops' antennas immediately go up. >> i think that's where police were suspicious so quickly, because of his behavior at the scene. >> reporter: christian boone covered the story for the "atlanta journal-constitution." >> when they arrived, someone else was doing cpr to cooper. he was talking on the phone to somebody. officer came up. he yelled at her. >> i need your i.d. >> for what? just hold on. shut the [ bleep ] up and hold on. my son died. all right, all right, all right, all right.

>> you need to watch your [ bleep ] mouth! stop fighting. >> if you drop the cuffs, i'll calm down. you have to understand i'm really upset. >> behavior was a little erratic. he was sitting in the back of the squad car alternately weeping or very distraught, and then, sort of looking around to see -- in their mind, they felt like he was putting on a performance, and not a very good one. >> one of the officers, the best she could describe it as was almost like will ferrell. one minute he would be yelling, "my boy, my boy!" >> what have i done? oh, my god! oh, my god! what have i done? my boy! >> next minute, he's calm. >> reporter: cobb county assistant district attorney chuck boring says ross' strange behavior continues in the back of that police car, complaining about everything from the cuffs -- >> they're really hurting me. >> reporter: to, believe it or not, it being too hot in the back seat. >> feels like i'm not getting any air back here. >> within a minute or two of you allegedly discovering your son deceased in the back of your car, and you're in the patrol car, complaining about how hot it is in the back of the car.

that struck police as well. >> reporter: how would you expect a grieving father who had accidentally placed his child in the backseat and left him there, how would you expect someone in that situation to act? >> i think it's fair to say that there's a spectrum of reactions. you can't say one person is going to react a certain way. >> reporter: and ross harris' behavior was out of that spectrum? >> it was absolutely outside the norm. >> reporter: when word spreads of ross' arrest, an outraged public quickly comes to his defense. >> the community thought it was just a horrific tragedy, that it was a horrible accident. i think a lot of people couldn't understand why the police were holding ross harris. >> reporter: and there's a reason why so many came to ross' defense. after all, it's not all that uncommon for children to die in hot cars. >> 3-year-old died. >> reporter: it happened s 43 times just last year. it even has a name -- forgotten baby syndrome. >> in a hot car. >> for five hours. >> for 16 hours. >> an unspeakable tragedy. >> reporter: in many cases these

deaths seem to be the cause of a parent in a morning fog, forgetting a daycare drop and that their child is still in the car when they park at work. >> franklin police say this little girl was left in the car saturday morning with temperatures soaring toward the 90s. >> reporter: but police think something more sinister is at play with ross harris. police bring him to cobb county police headquarters to be questioned by detectives, where his behavior continues raising eyebrows. >> in the interrogation room, i think i used the term "huffing and puffing" in there, because you see the beginning of it. he starts, he'll yell. >> oh, god! >> he'll start blowing really hard. and then he's just hanging around, looking around. once the police come in, start talking to him, it's very, you know, matter of fact. >> i just watched news reports. there was a news report of a guy

who did this, just like me. and now he's an advocate for when you park, you turn around and look again. and i've been doing that because the worst fear for me is to leave my son in a hot car. >> reporter: after police tell leanna what has happened, she heads to the station, and into the arms of her husband. they are both unaware police are listening, and watching this video. how will leanna explain her behavior towards the man who cost their son his life? a lot would be made over your reaction. how are you not angry? stay with us. ♪ ♪

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>> reporter: the very night ross harris is arrested, he's charged with the murder of his son, and held without bail. >> they threw my husband in jail, we weren't able to deal with the death of our son together. >> reporter: you never actually had a moment with your husband in private to talk about what happened? >> right. >> reporter: and the loss of cooper. >> never. >> reporter: and at least publicly, the police are being very tight-lipped about why. >> "what's going on? why is he being held?" there was an air of mystery. no one really knew what was happening. police weren't saying. >> reporter: 15 days later, in a packed cobb county court room, both the public and the press wait to find out why, unaware that both parents are about to be cast with suspicion. >> no one really knew what was coming. no one had any idea for the bombshells that would follow against ross and against leanna.

>> reporter: during the probable cause hearing, lead detective phil stoddard takes the stand for assistant d.a. chuck boring and begins laying out the police case that this wasn't just a typical accidental hot car death. how did this case compare to any other hot car case you've covered? >> what stuck out initially in addition to the obvious overabundant evidence of negligence was that these factors that you usually see did not fit in this case. >> reporter: like what? >> i would say to start with the position of the car seat and where the car seat was. >> what was the distance between the driver's seat approximately and the head area end of the car seat? >> six inches at the most. >> reporter: the car seat extremely close to the driver's seat? >> correct. >> reporter: ross had always told police cooper must have fallen asleep during that car ride. but boring points out ross' drive from that chick-fil-a to his job at home depot was merely a half a mile, not a long he n

of time. the drive, two minutes? half a mile? >> around that. 0.6 miles. >> reporter: but then police uncover something shocking. this surveillance video from ross' parking lot. that's him, caught on camera at 12:42 p.m. returning to his car, opening the front driver's side door, dropping off a bag of light bulbs. but ross never mentioned this important detail to the police. >> he gave a lot of detail about what went on that day. about his last interaction with cooper. he never once mentioned the trip back to the car. and that stuck out. >> reporter: and as detectives pour over every shred of ross' daily life. >> let's see just how hot it gets. >> reporter: they uncover this on his computer. >> this kills and it's a lousy way to die. >> reporter: it's a video about the dangers of leaving pets in hot cars, viewed by ross just days before cooper died.

>> detective, what day did he view this video last? >> he viewed it on june 13, 2014. >> five days before the child's death? >> that's correct. >> after however long it was, a couple of hours, the public opinion had shifted greatly. i don't think there was very few people outside of his friends and family who thought that he was innocent. >> reporter: but it isn't just ross harris detectives say acted suspiciously that day. they also publicly point to leanna, starting with that quick conclusion she makes after discovering cooper isn't at daycare. >> in front of several witnesses all of a sudden she states, ross must have left him in the car. >> reporter: and they say she is strangely unemotional when her fears are confirmed. >> there's really no easy way to tell you this. your son is deceased. >> where is my husband? >> when police spoke with her, did they say anything of note about her reaction at the scene? >> her reaction at the scene, she didn't show any emotion when they notified her of cooper's

death. >> reporter: and perhaps most suspicious of all to detectives, leanna's interaction with ross at the police station. >> she looks at him, she's like -- >> did you say too much? >> at first blush, that looks, like, "wow, what is that about?" >> reporter: leanna goes from grieving mother to possible accomplice by the time court gets out. >> the statements that were made by the detectives in that hearing, specifically about me, casted a big shadow of questions and doubt. >> reporter: but some of leanna's own statements raised big questions too. like the one she made at her son's funeral. >> at the funeral, she just didn't act like the -- you know, people thought she should act. >> i was trying to come to terms with what happened and there were things that i said at the funeral that people took and turned them into something that

i didn't mean. >> reporter: you said that cooper was in a better place. and if you could bring him back, you wouldn't, into this broken world. >> right. and anybody who knows me knew exactly what i meant. my faith is the only thing that has kept me alive since this happened. the only thing that could give me any kind of peace was knowing that cooper was in a good place. the things that i said at the funeral, there's no place for media at a funeral. i was burying my baby. reporters walked into the funeral and recorded what i said, and then took it out of context and made judgments on it. >> reporter: if you could bring cooper back right now? >> if i could bring cooper back, me, of course i would bring him back. >> a georgia man accused of intentionally leaving his

toddler son in a hot suv to die. >> was it an accident or was it murder? >> we're talking about a little boy left alone in that car for seven hours. rorter: when we come back, leanna fiercely defends herself. are you owed an apology? >> i'm absolutely owed an apology. >> reporter: but why would she still defend her husband? >> this is anybody's story who has been betrayed by their spouse. >> reporter: stay with us. to most people, i look like... most people. but on the inside, i feel chronic, widespread pain. fibromyalgia may be invisible to others, but my pain is real. fibromyalgia is thought to be caused by overactive nerves. lyrica is believed to calm these nerves. i'm glad my doctor prescribed lyrica. for some, lyrica delivers effective relief from fibromyalgia pain... and improves function. lyrica may cause serious allergic reactions, suicidal thoughts or actions. tell your doctor right away if you have these, new or worse depression, unusual changes in mood or behavior, swelling, trouble breathing, rash, hives,

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>> reporter: leanna harris is wondering how it could have come to this.

her son is dead. her husband, in jail. and now there's insinuations swirling that she too may have played a part. >> people looked at you and thought the worst. >> mm-hmm. >> reporter: unable, she says, to find solace or comfort, even at the most sacred of places. there was a card left at cooper's grave. tell me about that card. >> it basically said, "i'm sorry that you weren't loved in this life, cooper. if you had been my son, i would've loved you." it's hard enough to lose your child, but then to have to have people think that you didn't love him and that you didn't want him, that's something that should never be added to the equation of having to bury your baby. >> reporter: but the public perception was fueled by leanna's own behavior the day cooper died. and at his funeral, behavior she herself admits was suspicious. a lot would be made over your reaction.

or your lack thereof. people said you were emotionless. you didn't have any tears. >> there's no way for someone to know how they would react. if somebody had asked me the day before this happened, "how would you react if this happened to you?" my explanation of how i would have reacted and the reality of how i actually reacted would have been completely opposite. nothing about it felt real. nothing about it felt like it was happening. it just felt like a bad dream. >> reporter: and what about that infamous police video, with leanna embracing an accused ross at the station? you were compassionate towards your husband. which is something i think a lot of people look at and think, "how were you not upset? how were you not angry at him when you first saw him?" >> it never crossed my mind that ross had done it on purpose. never.

it was an accident. i was trying to react in a way -- i wasn't concerned about the police. my concern was reacting to ross in a way that would help him. >> reporter: but accident or not, he was responsible for the death of your son. how are you not angry? >> that wasn't sinking in. since that day, i have gone through all of those emotions. >> reporter: you've been angry at him? >> yes. >> reporter: and then when you said to ross -- >> did you say too much? >> reporter: why did you say that to him? >> i knew my husband. i knew his personality. logically, ross doesn't shut up. so the only thing that i could think of logically is like, "what did you say to make them think that you did this on purpose?" >> reporter: do you believe leanna had anything to do with her son's death? >> there is absolutely no

evidence that we could uncover she had anything to do as far as planning or killing this child. >> reporter: but police are building a case against ross, and it's unprecedented. formally charging him with malice murder, saying he killed his son deliberately. his weapon? that hot car. at what point did you know that this wasn't just a negligent homicide case? >> personally, fairly early on. >> reporter: and there would be bombshell secrets revealed about ross that would sink his credibility, according to d.a. chuck boring, one of the biggest discoveries is found over a year after ross is first arrested, a message he sends on the anonymous messaging app whisper the very morning he is with cooper. >> we found that the defendant had actually been messaging somebody in a conversation about not being happy being married with kids and him saying ten minutes before locking the child in the car to this anonymous person, "i love my son and all, but we both need escapes." >> reporter: and that's not the only thing they find on ross' phone. >> i mean, he was compulsively, like, you know, sexting.

i mean, the day of, he was talking, you know, with cooper in the car, to someone. >> reporter: that's right. it seems ross had been cheating on leanna virtually and physically with dozens of women, men, and even underage girls. it is a sordid and vile revelation that the prosecutor says ties the how to the why in this horrible case. what was ross' motive? >> he was living a double life. i think he just was having less and less time to live the life he wanted. >> reporter: october, 2016, ross harris' trial begins. defense attorney maddox kilgore argues cooper's death was just like all those other hot car cases we hear about. a tragic accident. >> ross has always acknowledged that this was his fault, that he was responsible, but what you're going to see during this trial is that responsible isn't the same thing as criminal. >> but the prosecutor has a

field day airing ross' dirty laundry because there's so much of it. >> messaging over 30 people, most of them women, and exchanged comments about being unhappy in his marriage. >> reporter: a man they claim was consumed with his sexual activities even as his son was dying in his car. >> while that baby was out there, he was showing pictures of his private parts to other people. >> have a seat, please. >> reporter: they march nine women out that ross had contact with, there was the former prostitute -- >> it was basically regular vanilla sex. >> reporter: the babysitter, the co-ed. >> he picked me up from my dorm room. >> reporter: a woman he professed his love for. >> i guess i had fell in love with him. >> reporter: women he sexted with frequently. >> i asked him if had a conscience and he said no. >> reporter: he even sent lewd pictures of himself to a 15-year-old girl. that had to be incredibly devastating. >> it is incredibly

disappointing to see somebody that you loved, somebody that you trusted, and somebody that you believed in go down a road of that kind of destruction. >> reporter: is it just disappointing? isn't it disgusting? >> yes. >> reporter: while no one should be more disgusted or disappointed with ross than leanna, the nation leans in with complete shock when leanna shows up as the star witness for the defense. you went on the stand and supported your husband. why did you do that? when we come back. around here, i'm lucky to get through a shift without a disaster. heads up! you know what, don't worry about it. my bargain detergent couldn't keep up. it was mostly water. so, i switched to tide pods. they're super concentrated, so i get a better clean. i mean, i give away water for free. i'm not about to pay for it in my detergent.

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>> reporter: glynn county courthouse, brunswick, georgia. the ross harris murder trial is being held 300 miles from the scene of the crime. defense attorneys argued for a change of venue to ensure a fair trial. >> i've described to a lot of people what happened to me was kind of like an earthquake. losing cooper was the massive damage, and then everything else after that was like an aftershock. >> reporter: ross' lawyers now march out a cast of characters from ross' brother. >> i think he loved cooper more than life itself. >> reporter: to a bible study confidante. >> cooper kind of became the center of ross' attention whenever he was around. >> reporter: to help paint a picture of ross as a caring and committed father, not a cheating, cold-hearted killer. but th spki ihifense. she took the stand in her ex-husband's murder trial. >> reporter: the courtroom is aghast as the grieving mother turned spurned wife takes the stand. now divorced from ross, and now back to leanna taylor.

she may be her ex-husband's last, great hope. >> did ross love this little boy? >> yes, he did, very much. >> reporter: you went on the stand and supported your husband. why did you do that? >> this was never about me defending ross. when you get on the stand and you swear to tell the whole truth and nothing but the truth, that's what you're supposed to do. and that's what i did. i couldn't get up there and say that he was a bad father because it wasn't true. i couldn't get up there and say that he seemed bothered by having a child because it wasn't true. >> reporter: but on cross-examination the prosecution zeroes in on ross' so-called double life, confronting leanna about ross' affairs and other lewd behaviors. >> you would agree that that was somebody completely different than the person you married? >> i would agree that that was a part of his personality that he did not share with me. >> reporter: but leanna dislikes the description of a double life, saying she there were struggles in their marriage, revealing she knew her husband had at times sexted with other

women and struggled with a porn addiction, that she says she believed was under control. she says they were in counseling when cooper died. >> did he ever tell you that he'd gotten up at 5:43 a.m. around there, was awake at that point, messaging strangers? >> no. >> reporter: but leanna remains steadfast that he would never have taken the life of their 22-month-old son. >> there was evidence in our relationship that would suggest that he would be capable of being unfaithful to me. there was no evidence in our relationship that suggested that he would harm anyone, much less his own son. >> reporter: was there ever any evidence presented at trial that made you question whether or not ross was guilty of murder? >> not guilty of intentionally murdering, not planning the murder. >> reporter: nothing about the two-minute drive? >> no. >> reporter: the proximity of the car seat?

>> the car seat would've been there whether cooper was there or not. >> reporter: him going back to the car? nothing made you think, "hmm"? >> the going back to the car part actually for me solidifies that it wasn't intentional. to me, it said the opposite. he didn't have a clue that cooper was in there. >> reporter: what about ross watching that video of an animal in a hot car in the days prior to cooper's death? >> we have a dog. many, many other people viewed that same video. >> reporter: many, many people didn't then leave their son in a hot car. >> right, you're right. >> reporter: but despite leanna's steadfast support for ross, there was this. the most raw and emotional confession she would make. >> how do you feel about your ex-husband? >> he ruined my life. he destroyed my life. i'm humiliated. i may never trust anybody again the way that i did. if i never see him again after this day, that's fine. >> reporter: after 26 days of

trial, over 70 witnesses and roughly 1,200 pieces of evidence, it's judgment day. >> we find the defendant guilty this 14th day of november. >> reporter: there's a hush in the courtroom as a jury of six men and six women find ross harris guilty of all eight counts, including felony murder. he is sentenced to life in prison plus 32 years. >> found guilty for leaving his son in a hot car. >> the judge delivering a stern message. >> delivering the maximum sentence. >> reporter: leanna continues to believe that the jury got it wrong, but she's beginning to come to terms with why they would have convicted him. >> i think that most people believe that somebody needs to pay for the death of a little boy. that's the emotional response to that. his actions that day resulted in my son dying, and that's the truth. >> reporter: has ross ever apologized to you? >> mm-hmm. >> reporter: what did he apologize for? >> for not protecting our son

that day, for not being faithful to me, for taking his family for granted. >> reporter: do you accept his apology? >> i accept it. it's not going to change anything. >> reporter: do you feel like you have closure with him? >> no. i don't really know what the closure would be. i've never had the opportunity to express the anger that i've had towards him. >> reporter: have you imagined what you would say to him? >> yes. i don't think it's appropriate for right now. >> reporter: meanwhile, ross harris is appealing his case. when we come back, how does anybody overcome such unimaginable grief? >> i've held a knife in my hand to my skin. >> reporter: what stopped you from doing it? stay with us.

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♪ ♪ real cheese people are they're hot and cold. big and bold. but they would never make a sandwich with pasteurized process cheese food. sargento slices are 100% real, natural cheese. sargento, we're real cheese people. >> reporter: these days, little gives leanna harris, now leanna taylor, solace. her son cooper has now been gone longer than he was alive. i know that you still have some of cooper's things with you always.

>> right now at this very moment, there is a sippy cup on my kitchen table that still has the water in it that he had drank the day before or the morning of. and i just can't -- i can't wash it. i can't empty it because it -- there's some of him in it, and that -- that may seem weird. it may seem -- >> reporter: it doesn't. >> it's on my table, and nobody touches it. it's like they know better. >> reporter: leanna has found another, more permanent way of keeping her son with her, everywhere she goes. >> i decided that i would have his footprint tattooed on my foot. i remember thinking, because there was suspicion around me, that if they took me, and they threw me in a jail, and they took everything away from me, they would never be able to take that footprint off my foot. >> reporter: you also have another tattoo on your wrist. >> the anchor was very symbolic for me.

i was trying to anchor myself in this life when i didn't want to be here. >> reporter: it begins with a semicolon. tell me what that semicolon represents. >> the semicolon is a representation of a place in your life where you could have put a period, and ended it. you could have ended your life. but you choose to continue that sentence and not end it with a period. >> reporter: how close did you come to ending it? >> i've held a knife in my hand, to my skin. i've held a handful of pills in my hand and weighed the options and the cost. >> reporter: what stopped you from doing it? >> my family. they've been through too much. and the hope that something could be changed because of what i went through, because of what happened to cooper.

that lives could be saved, and i have no control over that if i end my life. >> reporter: leanna, now remarried, is working on a docume documentary spreading awareness about forgotten baby syndrome. >> if you're just an outsider looking in, you're like, "well, of course that happened to him. he was a horrible husband. he cheated on his wife." maybe they might even say, "he deserved it." that perpetuates the thought process that this couldn't happen to me because i know i'm a good parent. just accept that it could happen to you and you're providing a safety for your child. >> reporter: so leanna hopes and prays she changed two narratives tonight. the one about her son's death and the one about some other child her message might one day save. what do you want for cooper's legacy, for his name, and your name, leanna? >> he deserves a better legacy than the boy whose father intended to kill him.

what if they were wrong? they were wrong about me. how is that justice for my son? how does that protect his memory? >> a powerful reminder for every parent. that's our show for tonight. thanks for watching. for david muir and all of us here at abc news, good night. breaking news, a new brush fire just broke out and homes

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