Transcript for 21-year-old Kelsie Schelling vanishes after meeting with boyfriend: Part 1
I think it's every parent's worst nightmare, that a child goes before you. The idea that someone can essentially disappear without a trace I think is kind of a counterintuitive thought for people to have. Reporter: It's the story of 21-year-old Kelsie shelling who went missing in 2013, and her mother, Laura Saxon's eight-year-long search for justice. Her family is pleading for your help. We are doing everything in our power to find our missing loved one. Reporter: Kelsie grew up in the farm town of Holyoke, Colorado. It's a carefree, happy childhood shared with brother Colby. She's been a firecracker. Reporter: As Kelsie enters her teen years, the family is rocked when Doug and Laura divorce. The split of our parents had an impact on both of us. She ended up in the hospital for several days, and it was pretty scary. She was on an anti-depressant pill and she ended up taking three of them. I thought we were going to lose her at that point. Reporter: Kelsie gets her life in order, moving on to northeastern junior college in sterling, Colorado. She wanted to get a degree in psychology. I think in her heart she wanted to work with children. Reporter: For a while, carefree Kelsie is back. Then she meets Donte Lucas. It was a big deal that she was dating Donte. He was part of the basketball team. They were kind of the popular kids and everything. When did you first meet him? I never met him. I saw him play basketball a couple times. He was not committed to her by any means. He would play with her heart. I could definitely see some bubbliness feeding out as he broke her spirit. Reporter: Donte and Kelsie date on and off. After leaving school Kelsie moves to Denver where she lands a job. Donte moves back to Pueblo. When did she start going out with Donte again? Over the holidays, November, December. He would stay with her, then go back to Pueblo sometimes. Were you worried he would come back and what that would do to her? Absolutely. She didn't want that to happen because she knew the kind of person she became when she was with him. Reporter: Around the holidays Kelsie has a surprise for her family, she's pregnant. I told her, I will support you. It's going to be okay. She was happy. Did she tell you anything about Donte's reaction? She said he was mad, very angry. Reporter: On February 3rd, 2013, Donte asks Kelsie to visit him in Pueblo. She says no. They continue to fight over Just before 3:00 A.M., Kelsie texted Donte, you don't have to be in a relationship with me, you don't have to marry me, you don't have to have a happy family with me, you don't have an obligation with me, you're good, don't worry, good night. Lucas' response, I know all of that, thanks for stating that for me. Reporter: The next day, Kelsie visits the doctor who confirms her pregnancy. What did you think when you saw the baby? I was happy. I knew that she was happy. That morning, Kelsie told Donte she had finished her appointment, due date September 13th. Lucas' response was cool. He asked her to skip work and come to Pueblo. She texted, I'm not going to come get you so we can fight. He texted, I don't want to fight, I want to give you this. She writes back, give me what? He says, wait and see for yourself, you probably wouldn't believe me if I told you anyway, you can see for yourself. Reporter: Kelsie decides to drive to Pueblo after work that night. She and Donte plan to meet the a local Walmart. She arrives at 10:20 P.M. After waiting for almost an hour, Donte is still not there. The two decide to meet near Donte's grandmother's home where he was staying at the time. The last confirmed message from Kelsie was 11:18, where are you, I've been here over an hour just waiting. Reporter: The next day, Kelsie doesn't show up for work. Over the next several days, family and friends grow worried. Kelsie's not answering phone calls. They say her text messages just don't sound like her. I'd called Doug, her dad, and said, something is wrong. Reporter: Kelsie's family drives to her apartment in Denver, but there was no sign of they eventually call the police, who reach out to Donte. He was telling me that he had seen her and talked with her and spent time with her more recently than any of her family members, friend. I did have a sinking feeling in my stomach. Reporter: Police turn the case over to the Pueblo police. When Donte is brought in for questioning, he denies a serious relationship with Kelsie. Came to Pueblo, we were talking. Reporter: Donte says Kelsie slept in her car in Pueblo, then he met her the next morning and they stopped at Walmart before she headed back to Denver. She went to go get some snacks, something to eat, she was hungry. Came back, we ended up talking. She ended up telling me to get out of the car at Walmart, she didn't want to take me home. I left the Walmart, started walking home. My mom came and got me. Reporter: Surveillance video shows just Donte getting out of Kelsie's car. The morning of February 6th, this unknown man is seen walking to Kelsie shelling's car and is seen driving away with the car. We have no idea who that person was in that video. Who do you think that someone was that came back and drove that car away? There's similarities to Donte, but it's nothing that we can say, that is the person that drove it away. Reporter: February 14, Kelsie's car is found in Pueblo, but no Kelsie. Police start working backwards, going through surveillance video. What they find is surprising. Less than 12 hours after she would have arrived in Pueblo, surveillance video shows Donte in her car at an atm in Pueblo, he's driving, he takes $400 out of Kelsie's bank account. Reporter: Donte is brought in for a second time by Pueblo police. When you dropped her off at Walmart, where were you parked at? Apparently you guys know, so I don't understand -- like I told you, I don't -- that's all I can say about it. Dropped off when was that again? Can I speak to a lawyer, please? Reporter: Once he requests a lawyer, all questions come to a halt. How did you read that? As the possibility that he knows something. Reporter: Donte's arrested on felony identity theft but the charges are later dropped after investigators find out Kelsie occasionally gave him permission to use her bank card. He's released. He's living his life. Do we suspect foul play? Yes. Have we come up with a body? No. Donte is a person of interest in the fact that she's missing. Reporter: Police speak to his mother about February 5th, the day Donte is seen on surveillance camera parking Kelsie's car at Walmart. Did you pick Donte up? I did pick my son up. Reporter: She gives Donte an Al buy for February 6 when the unknown man is seen moving Kelsie's car from the Walmart. No way that was him. No way. He was at home. I know my son. He's not capable of hurting anybody. Without a body or any direct evidence that tells us something happened to her, to a homicide, you know -- it may happen one day, but right now, we haven't had any evidence to reclassify it. Reporter: Kelsie's family grows frustrated with the investigation. Laura launching search party after search party. That turned into justice walks around the Pueblo police department and the district attorney's office. We appreciate you all so much. Your support keeps us going. Coming up next -- It was a homicide investigation, in our eyes.
This transcript has been automatically generated and may not be 100% accurate.