Sheborah Thomas' children had been temporarily taken away from her by child welfare officials in 2012 after one of them had been found wandering the streets with an intoxicated homeless man. According to court documents, Child Protective Services placed the children with their maternal grandmother.
A man closely connected to the family tells Eyewitness News exclusively that the Houston Police Department and Child Protective Services also paid the family a visit the day before Thomas allegedly killed her children.
The man, whose identity we cannot reveal, says that Thomas received a threatening message on her phone. "It was a serious threat. She wouldn't have behaved like this for something minor." He urged Thomas to call the police.
Officials from CPS and HPD were at Thomas' home for approximately seven hours on Thursday afternoon. By the end of the visit, however, the man says that Thomas felt reassured, saying that "God was on time, like always, to help her through this ordeal."
CPS did confirm that there was an open investigation, but could not elaborate on the nature of the visit.
"[I] had no idea she was going to go and this will be the end result," the man adds, saying that Thomas was a loving mother who had gotten it together since the 2012 incident.
On Sunday, investigators say that Thomas, 30, admitted to drowning Kayiana, 5, and Araylon, 7, in the tub after they came home from daycare on Friday evening.
After eating, Thomas drew water and called Kayiana in for a bath. Once the girl was in the tub, the mother says she grabbed the girl by the head and forced her underwater, holding her there until she stopped moving, investigators claim. After that, they say Thomas placed the girl's body on the bed and called her 7-year-old son into the bathroom and did the same thing to him. The boy, she allegedly told detectives, struggled, but then stopped moving. She placed him on the bed next to his sister, investigators say in court records.
VIDEO: Court documents reveal new details about kids' death
Authorities claim in court documents that Thomas told them later that night that she wrapped the kids' bodies in bed sheets and placed them in a black trash can behind the house. The following morning, Thomas says she got on the bus and went to work to try to get her check, but her employer would not give her a check early so she went back home.
Once there, she told detectives she attempted to bury the bodies between her house and her neighbor's house in the 3000 block of Tierwester. She told investigators she tried to use her hands and a piece of wood to dig a hole, but said the hole was not big enough and the bodies could still be seen.
Thomas said she rolled the children under the neighbor's house and returned to her home to pack because she planned to leave the house, according to court documents. That neighbor, Armando Selgo, is in shock, telling Eyewitness News in a translated interview, "It's very sad. It's incredible. We can't believe what has happened, what she has done."
VIDEO: Surveillance video shows mother day after she allegedly drowned kids
"The kids who are innocent and growing up and to have their mom do that to them. We think it's very sad," he added.
Selgo said he didn't talk with the family and he didn't know them well. He said the mother appeared to be acting normal on Saturday night and was smoking out in front of her home Saturday evening.
However, she did not appear to be behaving normally earlier in the day, according to her former boss.
VIDEO: Neighbor shocked after children's bodies were hidden under his home
In exclusive video, you can see Thomas walking into Little Cajun Kitchen at 1:30 on Saturday afternoon, less than 24 hours after she allegedly drowned her children.
Her boss, Santiago Wesley, fired her two weeks prior.
"She started complaining about working too much. She was complaining about not spending enough time with her kids and I'm like, 'I understand that. If you need time off, whatever talk to me,' but she just kind of blew up that day," said Santiago Wesley, owner of Little Cajun Kitchen.
He fired her after that.
On Saturday, she came in for her final paycheck, which amounted to $47. She wanted the check early, even though payday was two days later.
"For some odd reason, she spent two or three hours here, screaming and hollering, trying to get her last check. Just sweating. It almost got to the point where I was going to call the police on her, but I didn't, you know, I don't want to call the police," said Wesley.
VIDEO: HPD reveals details of double homicide in Third Ward
The case came to light on Sunday morning, when one of Thomas' acquaintances flagged down police. He told authorities Thomas asked him to help her move to the southwest side of town. He noticed the kids weren't around and he asked her about them.
She responded "matter-of-factly" that she had killed them.
HPD: Mother drowned two children in bathtub
The man said he thought she was joking, so he loaded his truck with her stuff. Once they drove away, he asked her again where the kids were, and she said, "On the side of the house."
He claims she replied, "I told you that I killed them." He says he then drove her back to her house while she went into detail about how she killed the kids and where she put them. He says he drove her around trying to gain her trust, and then he then parked near a police station and flagged down an officer.
Thomas has been charge with capital murder. She is being held without bond.
PHOTOS: Mothers with a deadly past
Child Protective Services says it is investigating the kids' deaths. The agency revealed it had previous involvement with the family, adding, "We cannot discuss details because of confidentiality and because of the current criminal investigation."
In a statement, CPS says, "It is important to learn everything we can about this tragedy, and what we can learn about what may have led to it, so our Office of Child Safety will conduct an independent and comprehensive review of how CPS handled any prior allegations involving the Thomas family."
CPS says a 12-year-old son was not in the home at the time of the incident, and has not been placed into CPS custody.
The Associated Press contributed to this report.
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