In a new ABC documentary about her pregnant daughter’s 2002 murder, Laci Peterson’s mother recalls her own mental anguish over the realization that Laci’s husband, Scott Peterson, might have been involved in her disappearance. 
 
 “It was very, very hard to even begin to suspect him, because in the back of my mind I kept thinking, what if he didn’t have anything to do with it?,” says Sharon Rocha in Truth and Lies: The Murder of Laci Peterson, which airs Thursday, September 14 (9 p.m. and 11 p.m. ET) on ABC. (An exclusive clip of the trailer is posted above.) 
 
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 “I mean, it’s not like this is a total stranger that you might be suspecting,” she says. “This is somebody that’s been a member of your family for several years now, and it’s really, you know, the back and forth and the guilt about feeling this way, and how it may have an effect on the relationship with my daughter if I’m wrong.” 
 
 “That’s the last person you want to think had anything to do with the disappearance of your daughter — her husband,” says Rocha. “The person that was a member of your family, somebody that you loved and cared about, and thought he felt the same way about your daughter. And knowing how she felt about him.” 
 
 The eight-months pregnant Laci, 27, vanished from the couple’s Modesto, California, home on the morning of December 24, 2002. Her body and the fetus of the unborn son they had named Conner washed ashore in San Francisco Bay four months later. 
 
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 The mystery and Scott’s headline-grabbing 2004 trial eventually exposed him as a killer with a mistress, Amber Frey. Frey’s emergence punctured Scott’s claim that his wife must have been taken and killed as she walked their dog while he was out that day on a solo fishing trip in the Bay. 
 
 Laci Peterson Family photo via The Modesto Bee/AP 
 
 Scott Peterson Justin Sullivan/AP 
 
 Scott Seeking Retrial 
 
 The two-hour ABC special — which also includes new interviews with investigators and those who covered the case — arrives as Scott Peterson continues to appeal the guilty verdict and death sentence he received 12 years ago. He currently is serving his time at San Quentin prison. 
 
 In his latest request for a new trial, Scott’s current lawyers raise doubts about the defense mounted by his then-attorney, Mark Geragos, and allege that a juror who voted to convict him lied in order to be picked for the panel, reports The Modesto Bee. 
 
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 In its 150-page response filed in court last month, according to the Bee, the California Attorney General’s Office counters that Peterson’s conviction resulted from “overwhelming evidence,” including: 
 
 “[H]is expressed wanderlust and desire to to be responsibility-free, which he conveyed to his mistress as the birth of his son neared; buying a boat mere weeks before Laci’s appearance; ‘fishing’ with the wrong gear on Christmas Eve morning in inclement weather; surreptitious trips to the marina in various rented vehicles after Laci’s disappearance; lies to friends and family concerning his whereabouts; the sale of Laci’s car and inquiry into selling their home, including furnishings; subscribing to pornography channels while the search was ongoing; Laci’s and Conner’s bodies washing ashore not far from Peterson’s location on the bay; condition of the bodies correlat(ing) with the timing of Laci’s disappearance; and (Scott) Peterson’s disguised appearance and possession of survival gear and copious amounts of cash at the time of his arrest.” 
 
 Mom Recounts Last Memory of Laci 
 
 In the ABC documentary, Laci’s mother describes the last time she saw her. 
 
 “She I and I were sitting side-by-side and Scott was sitting on the floor, and we were watching TV and she said the baby was kicking, so I put my hand on her stomach, because I’d never felt him kick,” says Rocha. 
 
 “I still didn’t feel him kick even when she said that,” she says. “But she leaned over to me and she said, ‘Mom,’ she said ‘Scott doesn’t like to do this.’ She said, ‘I’ve asked him about, you know, feel my stomach when the baby kicks, and he never wants to touch my stomach.’” 
 
 “That really, really bothered me,” she says, “and that was the last time I saw her.” 
 
 The special also promises never-before-seen home video of Laci, excerpts from Scott’s pre-arrest interview with Diane Sawyer, and anchor Barbara Walters’ pre-conviction interview with Scott’s parents. 
 
 Truth and Lies: The Murder of Laci Peterson airs Thursday, September 14 (9 p.m. and 11 p.m. ET) on ABC. ||||| The discovery of the bodies of Laci and Conner Peterson in April 2003 became a turning point in the investigation of Laci’s husband, Scott Peterson, for their murders. He was arrested days later and was convicted the following year, after which he was sentenced to die. 
 
 But, as with so much else about the Laci Peterson case, what authorities say happened and how Scott continues to describe it sharply conflict — a divide that is detailed in the ongoing A&E docuseries The Murder of Laci Peterson. 
 
 In an exclusive clip from the third episode, airing Tuesday night, both Scott and a detective on the case at the time recall how he reacted to learning that his wife and unborn son were found dead months after Laci vanished in December 2002 in Modesto, California. 
 
 “We told Scott. [There was] very little reaction on Scott’s part,” retired Modesto detective Jon Buehler recalls in the clip, adding, “In my view, because he was the one who killed Laci, there’s no reason for him to have a lot of emotion because he knew what the results were gonna be.” 
 
 • Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter 
 
 Laci Peterson Family photo via The Modesto Bee/AP 
 
 Scott Peterson in 2005 Justin Sullivan/AP 
 
 Buehler’s memory echoes what he previously told PEOPLE in 2005 about informing Scott of the bodies. 
 
 “He was not angry. He didn’t ask a whole bunch of questions,” he said then. “The only thing he said was, ‘Is that my wife and son?’ At that point it was sort of like, ‘Come on, Scott.’ So I said, ‘You know the answer to that question.’ Then he did fake sniffles [Buehler wiped his eyes and puts his head down to imitate Scott.] He said, ‘You told me what I needed to know.’ ” 
 
 Scott — a man once described as a “manipulator” by one of the jurors who put him to death — remembers this pivotal moment in his life differently. 
 
 As he explains in a call earlier this year from death row with his sister-in-law Janey Peterson, audio of which is in the clip above: “When they told me, I had just a terrible physical reaction. I mean it was a really emotional, physical reaction.” 
 
 • PEOPLE’s special edition True Crime Stories: 35 Real Cases That Inspired the Show Law & Order is on sale now. 
 
 “But I was in the car with those two detectives and I just stopped that,” Scott continues. “I wasn’t gonna let them see the emotions I was going through.” 
 
 Despite a successful — if largely circumstantial — argument by prosecutors that Scott murdered his pregnant wife while he carried on an affair with unwitting lover Amber Frey, who later testified against him at trial, he and his family have always maintained his innocence. 
 
 Not so, Laci’s mother told the Modesto Bee in April 2016: “There is absolutely no doubt in my mind that justice was served. Scott Peterson is guilty.” 
 
 His case is still being appealed. 
 
 The Murder of Laci Peterson continues Tuesday (10 p.m. ET) on A&E.
– Sharon Rocha was sitting on the couch next to her pregnant daughter, Laci Peterson, when the 27-year-old said the baby was kicking. "I put my hand on her stomach, because I’d never felt him kick," Rocha says in a new ABC documentary about her daughter's murder, per People. "She leaned over to me and she said, 'Mom,' she said 'Scott doesn’t like to do this.' She said, 'I’ve asked him about, you know, feel my stomach when the baby kicks, and he never wants to touch my stomach.' That really, really bothered me. And that was the last time I saw her." Peterson, eight months pregnant, disappeared soon after on Christmas Eve in 2002; her body and that of the son she was carrying washed ashore in California four months later and her husband, Scott, was eventually convicted of her murder; he is still fighting his guilty verdict and death sentence. In the documentary, which debuts Sept. 14, Rocha says the realization that Scott may have had something to do with her daughter's disappearance was a difficult one to accept. "It’s not like this is a total stranger that you might be suspecting," she says. "This is somebody that’s been a member of your family for several years now, and it’s really, you know, the back and forth and the guilt about feeling this way, and how it may have an effect on the relationship with my daughter if I’m wrong." She adds that Scott had been a member of the family she "loved and cared about," and that knowing how Laci felt about him made her not want to consider him a suspect. A&E is also currently airing a series on Laci Peterson's murder; People reported last week that in that series Scott Peterson was recently heard describing the "terrible physical reaction" he claimed to have upon finding out his wife and son were dead.