People.com Crime Chris Watts' 4-Year-Old Daughter Pleaded for Her Life After Watching Him Kill Sister: Lawyer Chilling new details have emerged in the murder of Shanann Watts and her daughters By Steve Helling Published on March 6, 2019 10:01 AM Share Tweet Pin Email The last few moments of Bella Watts‘ life were filled with terror and confusion. According to an attorney representing the family of Bella’s slain mother Shanann, the little girl begged for her life after watching her father kill her sister. On Tuesday’s episode of Dr. Phil, attorney Steven Lambert shared chilling details of the murder of the pregnant Colorado mom and daughters Bella, 4, and 3-year-old Celeste. While the family sat quietly, Lambert described the scene when Chris Watts strangled his wife before smothering the girls last August. Lambert’s account cites Watts’ confession to police from a Wisconsin prison on Feb. 18. According to Thomas Grant, another lawyer representing Shanann’s family, Watts confessed new details to investigators after finding religious faith. Lambert said that Bella walked in on her dad disposing of her mom’s body by wrapping it in a sheet. “[She] walked in and asked, ‘What are you doing with mommy?'” Lambert told Dr. Phil McGraw. According to Lambert, Watts quickly made up a lie. “What he said was, ‘Mommy is sick. And, we need to take her to the hospital to make her better,'” Lambert said. Watts then backed his work vehicle in to the driveway and loaded Shanann’s body before telling his daughters to get into the truck. They drove 45 minutes to Watts’ work site, an oil field. He buried Shanann while the girls watched from the truck. • 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. CDOC Behind the Scenes of Family Murderer Chris Watts’ Surprising Guilty Plea But the night of horror wasn’t over. “He walks over, takes CeCe’s favorite blanket, and smothers her,” Lambert told McGraw. “Then, he takes her body, takes it out of the vehicle. At this point, Bella had unbuckled herself from the vehicle. He went back to the vehicle. Bella said, ‘Please, Daddy, don’t do to me what you just did to CeCe.'” Watts smothered Bella as well, and disposed of the girls’ bodies in oil tanks. All three bodies were found three days later. In November, Watts pleaded guilty to all three killings. He is currently serving five life sentences without the possibility of parole. Watts was having an affair with a co-worker at the time of the killings. Authorities have cited his desire for a “fresh start” with his mistress as his motive. The Watts family. Facebook Chris Watts’ Mistress Breaks Silence About Affair — ‘He Lied About Everything’ A February 18 statement to PEOPLE from the Colorado Bureau of Investigation says that authorities “interviewed Christopher Watts for the purpose of developing further insight into the case. Watts provided investigators with additional information about the murders of Shanann, Bella, and Celeste during the interview.” A spokeswoman from the Colorado Bureau of Investigation tells PEOPLE the office plans to release more information on the case Thursday, adding that the office was taken by surprise by the Dr. Phil interview. A spokesperson for the Weld County District Attorney’s Office tells PEOPLE the office is not releasing any more information on the case.