i saw people. everybody is like this is what you would see in a movie. i still find it hard to believe that it happened. >> a bright, young woman murdered. >> i lost my best friend. >> a husband stabbed. >> she said, oh, my god, you're bleeding. >> the tragic end of a twisted love triangle, and a strange game. >> i'm not passing judgment, but when a game involves a blind fold and handcuffs. >> you want to think it's got to be sexual. >> two crimes, two mysteries that puzzled police until they found a link to one woman in love. >> she had her nails done that morning. she spoke to her friends that morning.

8:00 comes, we're still calling. >> we're waiting for you two. give me a call back as soon as you get this. >> we must have called her phone 25 times, if not more that night, looking for annalisa. >> so dinner went on without nelson and annalisa. >> driving home from the city that night, i said we should stop by the condo to see her, and for some reason we didn't. >> what christine and her friends could not have known was that someone else had gone to the condo earlier in the day. >> hello? a guy is -- attacked my neighbor. >> you think someone attacked your neighbor? >> a 911 call had sent police

rushing to anna lisa's home just after noon. tom mcginty would lead the investigation with greg holt. >> what did you find? >> the door ajar. you saw the female victim lying on her back and the scene of a violent struggle. >> reporter: it was annalesiona. she had been beaten and stabbed repeatedly, right in the middle of the day. >> there were plants overturned, dirt on the floor, very bloody scene. >> did it look like she had struggled? >> very much so. fought for her life. >> reporter: there was no sign of forced entry. the investigators figured annalisa had opened the door to her killer. was it someone she knew? >> and who was on the short list of potential suspects here? >> you always start with a small circle and go out. her small circle would have started with her boyfriend. >> nelson sesler? >> yes. >> police didn't have to go looking for nelson. he drove up to annalisa's complex right about the time

they were supposed to go to dinner. investigators broke the news to him and then told him to stick around. >> he was asked to wait outside and he was put in an area of the condo which is commonly referred to as the boathouse. >> reporter: about 700 miles away, local police in blaoomfied hills, michigan, were bringing the terrible news to her family. >> how did you learn that your sister had been killed? >> there was a loud knock on our front door. it shocked us out of bed. i went downstairs and, you know, there were police. it was hard to process that this had happened. i still kept thinking they couldn't have gotten it right. >> reporter: bernadette had to tell her parents. >> i said what, what happened to her? was she in an accident? i told her to be careful, you know. i was just shocked and crying. >> i felt so bad and so weak and it was just shocking. >> reporter: back in connecticut, stamford police were getting a surprisingly

different vibe from annalisa's boyfriend, nelson. >> was she emotional? >> if he was, he didn't show it to us. >> did he ask what happened to annalisa? >> never to us. >> no, not at all. >> never to us. in fact went to sleep. >> he went to sleep? >> went to sleep in the boathouse. >> as seasoned detectives, what did that say to you? >> it raised a big flag with us. big red flag with us. >> makes you wonder, did nelson know more than he was telling police about the murder of his girlfriend? and what would have been his motive for murder? no one could figure it out, especially his friends. >> how could he do this? why would he do this? it didn't make sense. >> neither did a strange game between a husband and wife, but it would provide a critical clue to solving the murder when "obsession" continues. [ male announcer ] what are happy kids made of?

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i lost my best friend. i lost my mentor. it didn't seem real. there's not a single person in this world that would ever want to hurt anna-lisa. >> maybe. but someone killed her, and it didn't look random. no burglary gone wrong, she knew her killer. >> who would possibly do this to your sister?

>> we had no idea. >> how do you even comprehend that as a parent? >> you can't. you can't. >> reporter: what they really couldn't comprehend was that anna-lisa raymundo was anyone's victim. she wasn't just physically strong, she was smart and cautious, not an easy target. so hard to believe that only a month before she died, anna-lisa and her boyfriend, nelson, were together at her sister's wedding, and everyone wondered was he the one. now he was at stamford police headquarters fielding questions about his girlfriend's murder. >> everything we tried to get from him, we had to pull from him. >> reporter: nelson said he slept at anna-lisa's the previous night, as he often did, and last saw her alive that morning when he left for work. he said he spent the rest of the day at the office. >> one of our questions to him over several interviews, if he had any girl friends, anyone else he was seeing at the time he was seeing anna-lisa.

he continually said no all the time. >> do you think he was holding back on you during that first interview? >> no question, no question. >> when nelson sessler leaves that interview, was he still a suspect? >> absolutely. >> reporter: but friends were baffled, nelson, a murder suspect? >> how could he do this? why would he do this? it didn't make sense. >> reporter: police took a long, hard look into sessler's whereabouts the day of the murder. >> we were able to obtain all his records from work, video of him at work. he left that morning in those clothes, came home in those clothes. >> no blood on those clothes. >> no blood, no marks. so we had him at work all day. >> so he had an iron-clad alibi. >> absolutely. >> reporter: so nelson sessler wasn't the killer, but the police still wondered about him. >> i didn't like him as the perpetrator in this, but i liked him for being right dead set in the center of this. >> reporter: by now other suspects were surfacing and tips

were coming in about one in particular. a sketchy guy who had been hanging around the docks. >> he had been seen by one of the residents in the condominium complex who also had a boat out there. >> reporter: his name was gary riley and he wasn't just seen the day of the murder, he was heard telling people things. >> he had talked to many people, giving them information about the crime, which kept coming back to us. >> and did you talk to gary riley? >> several times. >> and what did he tell you? >> he would deny what he told other people. >> reporter: police dismissed riley as a big talker and a stranger to anna-lisa, not a likely suspect. and remember the 911 caller? clearly she knew something. >> yes, hello. a guy is -- attacked my neighbor. >> reporter: the call had come from a pay phone just down the street from anna-lisa's house. >> you think someone attacked your neighbor? >> yes. i heard yelling.

i heard yelling. >> reporter: the woman calling didn't give her name and abruptly hung up. >> hello? >> reporter: police checked with anna-lisa's neighbors. no one could identify the caller. another dead end. >> was there a time when you thought this case may never be solved? >> oh, definitely. i felt like the police had no idea, no direction. it was just a mystery. >> so you've got suspicions about nelson sessler. you've got a 911 call. you've got a lot of blood and evidence from the crime scene, but no primary suspect? how long did this case stay that way? >> i'd say about five months. >> a long five months. >> reporter: and then on march 23rd, 2003, just across the connecticut state line here in westchester county, new york, another stabbing would change the course of the anna-lisa investigation. a woman brought her husband here

to the westchester medical center. he had been stabbed in the chest. and this couple's story was so flat-out weird, veteran police detectives are still talking about it. >> she originally tells me that, you know, paul had came home from work and he was injured. >> reporter: allison said while the husband, paul, was being taken to the e.r., she spoke with his wife, a woman named sheila davalloo. >> i sat down with her, she was polite, cooperative. >> he was like can you look at it? and i get nauseous. i couldn't look at it. >> reporter: but this case was about to take a hairpin turn, because the gravely injured husband was conscious and telling a very different story. he said he was injured while he and his wife were playing some sort of game at home.

>> what do you think about it? >> we were just playing a game. >> reporter: clearly something went wrong and police were about to learn that this game, this injured man and his wife would have a curious connection to the life and death of anna-lisa raymundo. coming up, exactly what kind of game was this couple playing? >> now, i'm not passing judgment. but when a game involves a blind fold and handcuffs -- >> you want to think it's got to be sexual. >> when "dateline" continues. the number one jewelry store in america. there are millions of reasons to give one, but the message is always the same. keep your heart open... and love will always find its way in. thank you. thank you.

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it had been five months since the stabbing death of anna-lisa raymundo in stamford, connecticut, and now -- >> i was in shock and i was holding it down. >> police in nearby westchester county, new york, were engaged in a bizarre conversation with a woman whose husband had been stabbed. the wife was fuzzy about the details, but the husband told investigators he had been stabbed while the couple was playing some sort of game in their home. >> you can blind fold each other, tie each other up and have to guess the object touching your body. >> the husband will never forget it. >> and what did this game involve? >> it was described as a guessing game where a person would be handcuffed and blindfolded. you couldn't see and you would have to try to guess what the items were. >> now, i'm not passing judgment here -- >> right. >> -- but when a game involves a blindfold and handcuffs. >> you want to think it's got to be sexual. >> you would think.

>> yeah. it's a good point. i wouldn't be afraid to say if it was sexual. but the truth is, it wasn't. >> kind of an odd diversion for two academics. the wife, sheila davdavalloo, wa research scientist. her husband was pursuing his doctorate in epidemiology. >> i was in school. she said she heard this game, she was bored, she wanted to play it. it would take a couple of hours. >> paul said sheila went first. she was handcuffed to a chair. he put a few items against her face. a camera, a shampoo bottle. she tried to guess what they were. then it was paul's turn. blindfolded, handcuffed, the whole drill. >> how long did it take until this game took a very bizarre, painful and dangerous turn. >> i'd say after about five or six items, i felt a heavy thrust on my chest. it almost felt like a dumbbell dropped on my chest. >> did she say anything to you?

>> i'd say after maybe three seconds passed, i felt another large thrust on the chest and then she said, oh, my god, you're bleeding. i think i hurt you. >> there wasn't a lot of blood and he said the pain wasn't severe so he wasn't sure what happened. >> i saw one wound and it didn't look deep or anything. i thought maybe she had a seizure and fell on me or did something, but now i've come back to reality because she's helping me get out of the chair. >> paul said sheila seemed to panic when he started to bleed so he took charge, telling her to call an ambulance. >> i said all right, call 911. she gets on her phone. i hear her my husband's been hurt, please hurry. >> in her conversation with the detective, sheila did seem distraught at times. >> tell me -- i want to hear what happened. you told me -- >> i don't know.

>> sheila, i don't want you to be embarrassed. >> i am embarrassed and i don't want to talk about this. >> it took a while, but sheila finally admitted to the game. she did cut paul, but said it was an accident. >> how did you accidentally slice him? >> we were playing and it got out of hand. >> i kept saying i just don't understand, sheila, you have to explain it to me. >> well, i don't believe you meant to hurt him. i'm not saying you meant to hurt him. >> sheila insisted she wanted to save paul's life, but after that 911 call, no ambulance came and that's when she drove him to the hospital. >> if i wanted to hurt him, i would have never come to the hospital. >> but it was at the hospital right there in the parking lot that the case of the husband,

the wife and the game took an unexpected turn. police spotted sheila's cell phone lying on the ground. you know, the one she used to call 911. >> i'm thinking i'm going to find 911 on the phone that she had called for help for her husband. we didn't find that call on the cell phone, but we did notice after he was injured that she called a gentleman by the name of nelson. >> in fact the detective learned while paul lay bleeding in their apartment, his wife never called 911. the only call she made was to anna-lisa raymundo's boyfriend, nelson sessler. >> so here's the question. why would sheila davalloo, who had just stabbed her husband, call nelson sessler? what's the link between those two? and what did it have to do with the murder of anna-lisa? >> two stabbings in a short period of time, and they were both connected to nelson. something does not make sense.

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i did not set out to hurt him. >> a woman named sheila davalloo stabs her husband during a weird guessing game and then of all people she calls nelson sessler, the boyfriend of a woman who had been stabbed to death just a few months before. co-worker and friend, christine dinerstein got the news right away. >> i get to work. i go sit down at my desk. someone comes up to me and tells me did you hear what sheila davalloo did? >> reporter: as it turns out, sheila davalloo also worked at purdue pharma. sheila was known as a competent biochemist and researcher, friendly, social, really smart. >> she was very successful. a lot of promotions in the company. >> reporter: the story about sheila and the knife swept through the office.

>> i've never heard of anyone getting stabbed in my life and here it is two stabbings in a short period of time. and they're both connected to nelson? something does not make sense. >> reporter: that's pretty much what detective carpentier was thinking. they asked nelson sessler to come back for another interview. investigator tom mcginty was there as well as sessler admitted that he and sheila davalloo were friendly. >> he was talking about how they were such good friends and used to go skiing and she had purchased two dogs. he would go over to her house and walk them for her. finally i said, nelson, nobody is driving from connecticut to westchester and not getting laid. finally he admits that he was having a sexual relationship with sheila. >> this was a bombshell. nelson was now admitting there had been another woman in his life.

he had dated sheila and anna-lisa at the same time, but said he broke up with sheila as things got serious with anna-lisa. that was a few months before the murder, and after the murder, he and sheila hooked up again. >> how did you react when sessler finally came clean to you and said yes, i was having a sexual relationship with sheila davalloo? >> i was very upset. >> i mean he's been working this case, anna-lisa's homicide day and night. the fact that nelson was keeping information from him was definitely upsetting to investigator mcginty. >> nelson sessler said he had no idea sheila had a husband, and the husband didn't know anything about nelson, until detective carpentier told her. she also told paul about anna-lisa, and that's when it clicked. that name, anna-lisa. >> sheila was always telling me a story about people at work.

>> it was an office love triangle. sheila said it involved her very, very good friend melissa, who was hooked on a guy who had a girlfriend named anna-lisa and sheila talked about it a lot. >> she seemed to want to tell everybody about it. she told me, she told friends of ours. >> sheila's friend, tammy may, heard about the office triangle and heard about it all the time. >> sheila would talk about her friend almost more than she talked about herself. almost to the point where she was obsessed with it. she would even talk about their sex life quite a bit. >> reporter: when sheila's affair with nelson sessler was uncovered, the fiction dissolved. >> jack turned out to be nelson sessler and melissa was sheila. >> reporter: so all of sheila's stories were about herself and her apparent obsession with nelson sessler. maybe nelson thought it was a casual fling, but sheila sure didn't, and it was only days after anna-lisa's murder that

sheila moved in on nelson again. >> according to nelson sessler, sheila began to bring him care packages a couple of weeks after anna-lisa died. >> it became very obsessive. when i think nelson learned the extent of the obsession, it became alarming. >> how would you best describe sheila davalloo? >> manipulative. >> manipulative. >> highly intelligent. >> and very good liar. >> reporter: so suddenly and for the first time, police investigating the murder of anna-lisa raymundo and a suspect with a motive, and they wondered if nelson sessler broke up with sheila to be with anna-lisa, how far would sheila go to get him back. >> coming up, she was clearly an obsessed woman, but is anybody this cold-hearted? >> she had her nails done that morning. she spoke to her friends that morning. >> it's like she had a list. nails done, talk to friends, kill my husband. >> and make sure nelson gets here by 8:30 so we can have dinner. >> when "dateline" continues.

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a woman with a motive. after five months of dead ends, the investigation into the murder of anna-lisa raymundo was heating up. police were learning that sheila davalloo had been obsessed with anna-lisa's boyfriend, nelson sessler. she had talked about him all the time and they believed she wasn't just talking, she was stalking. spying on nelson and anna-lisa. even her husband, paul, knew about it, sort of. >> to me it was like i'm helping my friend spy on a cheating boyfriend. that sounds fine, go ahead, do it. i even had these night vision binoculars i had from high school. i said take these, you can see in the dark pretty well. >> so if sheila was spying on anna-lisa by night, the next question was where was she on the day of the murder? police contacted purdue pharma, sheila had checked out of the

office that very morning. next they got a search warrant for sheila's apartment. >> we recovered packaging and receipts for two stun guns. >> two stun guns? >> she had a lock pick set and she had night vision goggles. >> and recording devices. >> reporter: police now had a theory. sheila davalloo was so obsessed with nelson sessler, that she stalked his girlfriend and went to her home to kill her. she may not have even needed the lock pick set. anna-lisa probably would have opened the door for her. >> this was not a spontaneous crime. this took a tremendous amount of planning. >> reporter: five years after anna-lisa's death, sheila davalloo was arrested and charged with her murder. >> it's like one of these lifetime movies where you hear about this kind of stuff. it's so hard to believe it. >> reporter: and sheila would say it's hard to believe because she was being railroaded. the evidence was flimsy. there were other suspects and the case was purely circuit shal.

>> ready to go? >> yes, we are, your honor. >> reporter: and when she finally went on trial this past february, sheila davalloo was fully prepared to take charge. she decided to represent herself. >> she's so arrogant that she thinks she can actually do better than her own lawyer. >> reporter: but she did sound the part. >> good afternoon, ladies and gentlemen of the jury. if i can approach the witness, your honor. >> reporter: she was polite, professional. >> no further questions. >> reporter: and so steady. this educated, friendly, mild-mannered woman was the same one who viciously stabbed anna-lisa raymundo to death? exactly, according to the prosecutor and police. she planned the killing, she carried it out, she covered it up. nelson sessler, the one-time suspect, was now introduced to the jury as just another victim of sheila's lies and manipulation. >> at any time prior to march 23 of 2003 did she ever tell you

she was married? >> no. she never did. >> reporter: and the low-key demeanor that police had once found so suspicious, now it seemed that's just how he is. >> he's very laid back. he's too laid back. people right misinterpret that for being not emotional at all or not caring. but i think he does care and he did care. >> reporter: he just didn't notice, according to the prosecution, that sheila davalloo's feelings were so intense. he even seemed clueless when in the summer before anna-lisa was killed, sheila suddenly showed up on his flight from las vegas. >> as i was waiting there, i looked up to see sheila davalloo walk up to me. >> at the airport? >> at the airport. there she was, and she was on the same flight as me coming back to -- >> where was she sitting on this flight. >> next to me. >> was this a complete surprise to you? >> it was a complete surprise to me. >> reporter: but sheila's friend, tammy may, knew this was

no coincidence. sheila had told her stories about hacking into sessler's voice mail. she knew exactly where she was going to be. >> she pretended as if it was destiny or fate. >> reporter: she was so manipulative, the prosecutor suggested that once she killed anna-lisa,he used nelson's grief to seduce him again. >> sheila was one of the few people that i knew in stamford that actually, you know, was willing to talk about it. most people sort of shunned me. i didn't have a whole lot of friends here to talk about it. >> reporter: but the prosecutor had to show the jury that not only was sheila davalloo obsessed with nelson sessler, she was willing to kill someone to have him to herself. and that's why the testimony of paul cristos was so important. >> it's so surreal, that when i look back, i can almost look at it in the third person. >> reporter: the prosecutor argued that when sheila davalloo rekindled her affair with nelson, her husband, paul, was

now in the way. she staged the game, she stabbed him and agreed to drive him to the hospital, albeit slowly, because she hoped he would bleed to death on the way. paul told the jury how he begged her to hurry. >> i can't believe how long it's taking. >> reporter: when they finally arrived and he was still alive, her deadly intention became clear. time was up for paul. >> she came in through the driver's side rear door. at that point she lunged at me and stabbed me in the chest. >> and now you're really bleeding. >> reporter: ythis time she nicked his heart. >> what are you doing, oh, my god, you're trying to kill me. >> reporter: and remember that call she made to nelson after she first stabbed paul? she was inviting nelson to dinner for that very night. paul, who is now divorced from sheila, finds the whole thing unbelievable. >> she had her nails done that morning. she spoke to her friends that

morning. she's not like taking the morning off or anything, she's doing her normal things, then figures she'll get rid of her husband. >> get nails done, talk to friends, kill my husband. >> make sure nelson gets here by 8:30 so we can have dinner. >> reporter: so now if the jury was wondering if sheila davalloo would actually do this, the prosecution's answer was yes, because she did this. and where there was motive, the prosecutor argued, there was opportunity. the jury heard how sheila checked out of her office the morning of anna-lisa's murder. she had no alibi. and remember that mysterious 911 call that came in minutes after the murder? >> i think a guy attacked my neighbor. >> reporter: police believe the caller was sheila davalloo herself. the prosecutor said voice recognition software showed it was indeed the defendant. >> that call was intended obviously as a matter of common

sense to throw the police off her trail. >> reporter: the prosecution had a suspicious 911 call, no alibi, and a killer motive. but was that enough to put sheila davalloo away? coming up, sheila davalloo was about to do something perhaps never before seen in a courtroom. cross examine the ex-husband she tried to kill, and the man she allegedly killed for. and coming up next friday on "dateline," three inspirational women. she's the powerhouse voice from nbc's hit show, "the voice." now things get personal. >> how do you make it work? >> it's an intense juggling act. >> she's a star in the hit drama "gossip girls" but her latest drama is all too real. separated from her children. >> all the things that we worry about every day don't matter. what matters are your babies.

>> actress kelly rutherford's heart-breaking battle. and she's the fashion blogger who battled back from a devastating plane accident. >> i was just thinking, wow, life can change in an instant. >> how lauren's bravery has touched the world. go!

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the case against sheila davalloo was loaded with motive. love, rage, obsession. but the prosecutor needed evidence that put her at the scene of the crime. and that's where a cut on sheila's hand came in. sheila's friend, tammy may, testified she noticed the ugly gash just a few weeks after anna-lisa's murder. >> i was like oh, my goodness, what did you do? she said she cut it on a can of dog food. >> reporter: but what if she cut herself during the murder and left some dna behind. police checked sheila's dna against some blood found at the crime scene.

investigator mcginn ty could hardy contain himself. >> do you remember your exact words? >> his exact words, "we've got her." >> sheila's dna was found on a drop of blood on a sink handle in anna-lisa's bathroom. >> there is only one explanation for that. that is she did this crime. it is consistent with guilt and only guilt. >> but it was just one tiny drop. was that enough to convince a jury? >> i'm claiming my innocence. >> reporter: not if sheila davalloo had her way. >> this is a case where i am being accused of killing somebody. >> reporter: as sheila davalloo presented the case for her own defense, she boiled it down to this. the state's case is flimsy, the evidence isn't there, and i'm not the villain they're making me out to be. with the respected public defender assisting, she listed the weaknesses of the prosecution's case. >> no hair evidence. >> reporter: the fact is from that terrible scene of violence and death -- >> no fingerprints.

>> reporter: there was no physical evidence with the exception of that one sample of dna -- >> search of my car yielded nothing. >> reporter: that puts sheila in anna-lisa's apartment. and even that couldn't put her there on the kday of the murder >> did the state prove to you that i was there on that day? they can't do that. >> reporter: what about the 911 call that supposedly put her just a few blocks from the murder? the prosecution said the caller was probably the defendant. people who knew sheila testified it was hard for them to tell. >> parts of it sounded like sheila and then a little part of it didn't sound like her. >> when you heard that 911 tape, what did you think? >> i couldn't really be sure. >> reporter: and her lack of an alibi, sheila said there was nothing suspicious about the fact that she left the office the day of the murder because she left the office all the time. >> on september 30th, i left work for four hours. on october 2nd, i left work

around the same time for two hours. >> reporter: she argued that once the police settled on her, they lost interest in any other suspects. she called gary riley, the petty criminal who had been seen in the area the day of the murder. he said he saw a fight going on between a woman and a man near anna-lisa's apartment the day she was killed. >> and i seen a lady and a guy arguing. >> reporter: as for the attack on her husband that culminated here at the westchester medical center, sheila said it had nothing to do with anna-lisa raym raymundo or nelson sessler. she told us she had been depressed, abusing prescription medication and out of her mind when she stabbed paul. when she faced her ex-husband in court, she implied that she had been mentally impaired. >> you stated that when i lunged at you, i looked distressed. >> correct. >> and you have previously

stated that i looked kind of crazy at that time? >> crazy, angry, correct. >> what was that like to sit on the stand and be cross examined by sheila? >> it was weird. who knows what she's going to say. >> she even asked paul, the man she stabbed, to comment on her supposedly gentle character. >> and you have said that i never wished harm on other people, even those i disliked? >> correct. >> after the ex-husband, she moved on to the ex-lover, telling the jury she was never hung up on nelson sessler. >> we had a summer fling. summer fling over a year before miss raymundo was killed. >> and when sheila davalloo finally faced nelson sessler during her cross examination -- >> good afternoon, mr. sessler. >> she seemed ready to throw him right under the bus, reminding the jury that he had once acted like he had something to hide. >> you had lied to the police?

>> yes, i wasn't forthcoming to the police. >> and what was the nature of that lie? >> i hadn't told them that you had been my girlfriend in the past and we had a relationship. >> right. and you did that why? >> i didn't want you to go through the ordeal that i had gone through. >> reporter: and then without presenting any evidence to back it up, she suggested nelson might be the killer. >> on the day of miss raymundo's murder, mr. sessler, you had a swollen red knuckle, a red mark on the side of your face wrapping around your ear and scratches on your back, correct? >> not to my knowledge. >> reporter: over the two and a half week trial, the jurors heard the testimony of an ex-lover, an ex-husband, and hours of technical testimony about evidence, dna and a woman's voice, and then the jury

got the case. >> i refused they would not find her guilty. >> but the prosecutor prepared your family for that possibility? >> yes, he did. >> reporter: a day passed. no verdict. on the second day, the jury came back. >> will the defendant, sheila davalloo, please rise and face the jury. what say you, mr. foreperson. is she guilty or not guilty? >> guilty. >> reporter: guilty of murder in the first degree. two months later, anna-lisa's got their say at sheila davalloo's sentencing. >> i would have repeated nightmares of seeing anna-lisa desperately crying out to me for help. >> she broke my heart. our family will never be complete again. >> reporter: and then it was sheila davalloo's turn. >> i'd like to ask some things for god, thank my family for their continued support.

>> she thanked everybody. she thanked the prosecutor for being an able adversary. i'd like to thank everybody in the department of corrections in new york and connecticut. >> she stood up there as if she'd won an award. >> reporter: she even addressed the raymundos. >> i pray for them and hope that this punishment your honor will hand down today will bring them some kind of closure. >> she made it sound like i didn't do it, but if you're going to give me this sentence, i'll do that for you. i mean that's the sheer arrogance. >> reporter: in the end, the judge sentenced her to 50 years. but here's what the jury was never told. at this point sheila davalloo was already serving 25 years in new york for the attempted murder of her ex-husband. when that term is finished, she'll be sent to connecticut to start serving her sentence for anna-lisa's murder. for now she is working on her appeals.

the case has created an unexpected bond between paul cristos and anna-lisa's parents. >> we are very grateful to him. >> in fact i told him i almost am not happy that you got stabbed but on the other side if you didn't get stabbed by your wife, anna-lisa's case would have been a cold case. >> i try to make them feel better and i said what's a little stabbing between friends. it was a paring knife, whatever. >> i tell people what happened and everybody is like this is what you would see in a movie. i still find it hard to believe that it happened. >> you look just like her. >> bernadette and her husband now have three children that brought life back to this family. >> for a pine cone to grow, it needs aer f foforest. >> their first born was given the name annalise. she's funny, smart, just like her aunt.

>> what do you want people to know most about your sister, anna-lisa? >> my sister was one of the most loving people that you could ever meet. everybody that she came in touch with has wonderful memories of her. >> you could picture her as princess or climbing a mountain or you could picture her playing tennis. >> she would always want to be the best at everything she did, and she was. >> that's all for this edition of "dateline." we'll be back again next friday at 10:00, 9:00 central. and i'll see you tomorrow on "today." i'm lester holt. for all of us at nbc news, good night.