Cases were colder than a grave. Youre always trying to make the pieces fit together nothing fit but one former cop couldnt let go. This is crazy this isnt solved. Reporter and one woman couldnt forget. The warning signs were there. Reporter two victims with one link in life. It was an obsession. It was control its the same mo. Reporter could a break in one murder help solve another . Things started fitting. Were getting to the end. Reporter im lester holt and this is dateline. Heres Josh Mankiewicz with fury. Reporter the kansas river separates kansas from missouri. But it also divides more than that. Theres a family on each side. And for a long time, each has been separated from the truth. And from each other. Each thought they were alone in wanting answers to the same questions. Outraged that ive gone years without ever knowing connecting them and getting closer to those answers took more than a quarter century. Unless you go through this, you have no idea what its like. This is how it happened. And how it began. Reporter it was december 29, 1989, in kansas city, kansas. A train conductor found the body. Right alongside the railroad tracks, under the highway. This just seemed like it was somethin right out of a crime scene book. Reporter at only 19, police cadet jeff cheek had already been to a few homicide scenes. But now he was looking at the body of a girl about his own age. The body was behind the pillar. So hidden from the road . Obvious attempt to hide her from the road. Reporter the victim had been stabbed to death. Her name was sarah de leon. She was eighteen. Just horrible scene. It was it it just was horrible. It was just reeked of evil. Reporter jeff realized theyd gone to the same high school. Id never talked to her. But i said, i do think i recognize her. I think i remember seein her in the halls i just remember it hittin me like a ton of bricks that this is this is a young girl. Reporter this is sarah de leons mom, gail. She was just just a good, quiet, funloving girl. She was healthoriented. She didnt even drink caffeinated beverages. When you worried about her and every mom does, whatd you worry about . I was concerned about her going away, just growing up, going away to school. Dating, meeting someone. Reporter sarah and her younger brother, matt now 44 were only a year apart. You guys get along . We got along really good. I played tennis at the high school and she would come to my practices and sit on the hill and watch me practice. And not a follower. People wanted to be like her, you know . She was, like, a trendsetter. She didnt care what other people thought. Reporter that december, sarah had just finished her first semester at community college. She was intrigued by other cultures and hoped to one day work in the travel industry. Everything was coming together for her so well. It was just coming together so well. Reporter she had a serious boyfriend, even introduced him to the family. She and her boyfriend, came over for a christmas party. It it was wonderful. And she didnt want to leave. She stayed and she told me she loved me and gave me a big hug. And it was it was just beautiful. Reporter that wednesday night was the last time gail saw her daughter. Friday afternoon, two Police Officers were at her front door. They came in and asked me if i was sarahs mother. Yeah. And they told me that they had found her body by the railroad tracks. And that she had been murdered. Reporter jeff the young cadet didnt just know the victim, he also knew that spot down by the tracks. This was an isolated area. I told the detective it used to be a party spot for kids our age and older. And the reason why there were parties there is because they knew it was isolated from the police. So High School Kids went out there right. To drink beer and smoke not to be caught. Right, so immediately i was kinda thinkin in my mind, who else knows about this place . Reporter gail could not fathom what her sarah might have been doing there. She didnt put herself in risky situations. You couldnt have imagined her doing drugs. No. Or drinking. No. Reporter police tried to retrace sarahs steps. Her boyfriend told cops theyd gone out for dinner that evening, and when sarah left his place in her car late that night, he said, he never saw or spoke to her again. And the next time anyone saw sarah de leon, she was dead. Killed somewhere else and dumped Somebody Just pulled up, dragged her out of the car . Right. Thats what it appeared to be. It looked like the car stopped out here, and you could see the drag marks all the way around. Reporter there was nothing to suggest that sarah had been at those parties down by the tracks. But when word of the crime spread, jamie locke, 20 at the time and familiar with the local party spots, says it was terrifying. The eerie feeling was the fact that, you know, where she was found. The place where you guys went to party . Yes. Reporter so, was it someone sarah knew or something random . Jamie remembers that some thought that it might have been a bumpandrob. Someone was bumping into cars, you know, little fender bender and then robbing them. After you pull over . Yeah. After you pull over. We did have a number of those at the time. You get out of the car. And they go, thank you. Im takin your car. They leave you there. Bump and rob turned bumpandmurder . Sarahs car was found abandoned at this overpass, miles from where her body was dumped. The police did take sarahs car, put it up on a rack, and look at the springs and the shocks to see if it looked like it had been bumped. That does kinda fit with some things that were going on at the time. Yeah. That would fit. I mean, its out there. The police are considering it. But that didnt fit, for me. Reporter it didnt fit she said, because detectives told gail how many times sarah had been stabbed. Too many to count. The passion in this murder, i who hated her that much . cause thats fury. It was real fury and hate with a passion. That was personal. Reporter it was that mothers intuition that would fuel a search for the truth. It would take many years and it would lead to the other side of that river. Saras boyfriend was a person of interest, but there was another. His exgirlfriend. When we come back, there was animosity there. Jealous. But whoever it was, didnt leave many clues behind. No fingerprints. No tire tracks. No witnesses. And no witnesses. Walgreens has you covered. So drop by and seize the savings walgreens. At the corner of happy and healthy. Its a mosaic of all the faces before it. Only true match has loreals technology to match your skins unique tone and undertone. 100 guaranteed. And its perfect. From loreal. 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Jeff cheek, then a cadet, says the pieces werent falling into place very easily. They didnt find a weapon. Reporter no fingerprints . Couldnt get fingerprints from anything. Reporter and no witnesses. And no witnesses. Reporter what do you do . I know they were looking at robberies. Whether it was kind of a process of elimination. Friends threats you start developing motives. You Start Talking to people in the inner circles. That s thats really how you work that kind of a homicide. Police briefly considered the possibility that sarahs death had been the result of a bumpandrob carjacking. To jeff cheek, that didnt make much sense. In this case, they left a perfectly good car behind. Bumpandrobs dont do that. They dont kidnap you, take you somewhere, kill you and then leave a perfectly good car behind. So they started working through sarahs inner circle. First up, her boyfriend matt uland. Reporter did you know her boyfriend . I met her boyfriend and, and i didnt spend a lot of time with him. He seemed like a good guy. To matt in the hours before sarahs body was found. Sarahs boyfriend called the house. And i said, hello. First thing he said was, do you know where sarah is . So, you know, i was, kind of, like, no. They questioned him. Of course thats one of the first things you do. Whos the last person to see her alive . And his answer was, i dont know anything about this. He said hed spent the the night with her. They had went to dinner. The boyfriend told police that after sarah left his house around midnight, he was home all night. And his mother backed up that alibi. Matt, her boyfriend. Uhhuh. Reporter do you suspect him . I didnt. And i didnt know him that well. But hed just been at the house. He seemed like a decent kid. His mother said that he was home at the time. I i believe that. I didnt see him as as a suspect. Reporter but when that happens, you got to start looking at everybody in her life. You do reporter thinking maybe ive maybe ive m everybody id go to the store and everybody there was a suspect the back of my mind it was like a computer going 24 7, trying to fit the pieces together with what little i had. Sarahs friends confirmed what her family had said sarah was popular. A leader. A good kid and a good student. Police did hear one weird story from a few kids in town about a girl who asked a male friend to help her do something mean to sarah. Reporter somebody had encouraged this guy to put something in sarahs drink . Yes. Reporter to what . At a party. Reporter knock her out . Yes. Reporter so that . She could cut off her pretty little hair. Thats what i got. This girl who police heard wanted to drug sarah and cut off her long hair . She was sarahs boyfriends ex there was some animosity there. Reporter jealous. Jealous. Jealousy. The police asked me if id heard of this gal. I said no. But apparently she had threatened to cut sarahs hair. Was sarahs death some of sophomoric prank that went too far . It seemed crazy, but police went ahead and interviewed the girl. It led exactly nowhere. Meanwhile sarahs mom did everything she could to help the investigation. Even going on a tv show called missing reward to plead for information. Somebody has to know what happened. And im just asking for them to let the authorities know. Its hard to come to terms with the death of your child when you dont really know what happened. Before long, the investigation seemed as cold and empty as the place where sarahs body was found. I was told there was just nothing. Reporter and you get the feeling the police think were not going to solve this. They had no no clues is what i was told. Reporter could you live with that . I was living with that, yes. That we would never. Jeff was still on the police force. Although not assigned to the case. I talked to the detective id say, hey, what happened with the de leon case . Did you get her did you get that solved . He said, no, you know, we havent got it yet. Reporter disappointing. Oh, yes. Very disappointing. Gail faced life every day without sarah, and without answers. And that lasted five years. Thats when another family in the same area found itself in the same darkness. Another young woman was dead. Another case with no answers. Coming up, a mother murdered. She was walking towards the kitchen. Thats when i heard the gunshot. And a husband with a secret when dateline continues. [burke] and we covered it, february fourteenth, twentyfifteen. Talk to farmers. We know a thing or two because weve seen a thing or two. We are farmers. Bumpadum, bumbumbumbum i cant work out without immy music ata again im telling you, you need to switch to sprint. I got unlimited data, talk and text for 50 bucks a month vo get sprints unlimited plan for 50 a month. Plus, get the Samsung Galaxy s7 edge and save 300. For people with hearing loss, switch to sprint. Visit sprintrelay. Com but with this usp seal i know seaexactlyap. Whats in my nature made gummies. Nature made has the first gummy certified by usp. A Non Profit Organization that sets purity and potency standards. Trythe unique formula withched nourishing almond oil. Leaves skin smoother. Moisturized for 24 hours. Nivea essentially enriched. For noticeably smoother skin. Woo called your own number . Are you bringing the thunder . Chorus theres a big mac® for that. On the edge of your seat . screaming beat . Chorus big mac® for that. Only in it for the halftime show . Its ok we know. Chorus theres a big mac® for that. Got into formation . Pumped up the nation . Got your own celebration . Ow juicy, cheesy, iconic big mac®. Now in three sizes, but only for a limited time. screaming man, im lovin it® ba da ba ba ba reporter sarah de leons murder had been cold five years and now once again, it was a frigid night. Super bowl sunday, 1994. Just about everyone had the day off. Except, perhaps, for the cops on the night shift. Patrolling independence missouri, across the river from kansas city. They spotted a car around midnight. Lights on, engine running, abandoned in a Church Parking lot. A quick check of the plates told them the cars owner, 26yearold diana ault lived in house a mile away. They say i have her nose and her hands. Thats the best compliment really. Reporter katie ault is dianas daughter. Shes now almost the same age as her mother was back then and like her mom in more than just looks. She used to work several jobs and do direct sales. She was always so busy and a lot of people tell me im the same way. Just lookin back at pictures it does bring back back memories, reporter this is dianas son, josh. My dad worked nights, and sometimes shed let me stay up watchin tv and, waitin for dad to come home. Reporter dad was tim ault. He worked at a Postal ServiceBulk Mail Center and was pulling a night shift that super bowl sunday. Josh was just 4yearsold, his little sister katie in diapers. Diana and the kids watched part of the game with family, the Dallas Cowboys versus the buffalo bills, and then headed home. Reporter tell me about that night. I remember coming home and it being dark. I remember going into the house, heard my mom going back out to the car for something, whether it was groceries or a bag diaper bag. Reporter kid stuff. Yeah. Memories are fuzzy, but not what happened in that very next moment. As she was walking through the livin room to towards the kitchen. Thats when i hea heard the gunshots. Reporter gunshots. And then, fouryearold josh saw the shadow of his mom collapsing onto the kitchen floor. Police later theorized the shooter had been waiting inside the house when the family got home. Very quickly after, i was picked up by somebody. I cant remember the details as far as what the person was wearing or the body structure or reporter whether it was a man or woman . Yeah, i i i cant remember. Reporter he says the person who scooped him up wore a mask. And then gently carried him down the hallway and into his parents closet. It wasnt like they just picked me up, threw me over their shoulder, and threw me in the closet. I mean, th reporter they they were holding you like like like youd hold a baby. Right. Reporter how long were you in that closet . I dont know. Finally working up the courage to come out. And i can remember seeing my sister crawling on the floor in the area of my mom. And ive been told that i tried to make my sister a bottle or comfort her. Reporter the killer had left in dianas car, so when police found it in the Church Parking lot and then traced it back to the owners home, they found a fouryearold giving a bottle to his baby sister. Their dead mother lying next to them. Grandma told me that i had a really brave older brother, and that even after everything that happened, he was still trying to take care of me. Reporter late that night, dianas father got a knock on the door. So as i opened the door, tims father was standing there. And the first thing he said when i opened the door was dianas been hurt. And shes dead. Reporter he immediately called his other daughter, sharon. I just remember sliding down my stove, just with this gutwrenching scream cry. It was ill never forget it. Reporter sister sharon and her dad, and dianas husband tim, rushed to the police station, where police asked tim the obvious question. Who would want to kill your wife . Tim said he had no idea. One more thing, the murder weapon was one of tims guns, taken from the house and left in dianas stolen car. Tim said none of it made sense. Tim was sayin that they had a good marriage, everything was good, they got the two kids, and things couldnt be better. He couldnt think of anyone who would want to hurt her. He didnt understand why this happened. Reporter detectives told the family the working theory was a robbery gone bad. But dianas sister responded by telling the Police Something they did not know. She said tim and diana did not have a great marriage. In fact, she said, tim had been cheating on diana. And just a month earlier on Christmas Eve, hed h the other woman. She was very upset about it. So and i i just remember thinking, on Christmas Eve . Really . Reporter that other woman was a coworker of tims from the Postal Service. Dianas sister sharon also told the cops that after a very unhappy holiday season, tim had ended the affair and moved back home. This detective sat there like he was just shocked. He hadnt ever heard this. And i ask. I said, is tim still here . And he said, yeah. So i said, go ask him if what im sayings true. And he confirmed it. Reporter so police spoke with both tim and his mistress. Questioned both of them. Tims alibi checked out. He was at work. And the other womans alibi was good, too. She said she was more than 100 hundred miles away. The case remained unsolved. Diana aults children were raised by their granar their father, tim. I remember asking josh, you know, why we didnt have a mom. And, you know, all your friends, you go to their house, and and they have moms. But he was the one who kind of first said, shes not here because someone took her. Reporter so now fast forward twenty years. Diana aults children are grown. Son josh newlymarried. Across the river in kansas city kansas, frustration is a feeling that the other family, sarah de leons family, has grown