A 30-year-old Texas woman is in custody on murder charges after the bodies of her two young children were found hidden under a neighbor's home. (Reuters)

With short pigtails and a wide smile, 5-year-old Kahana Thomas was reportedly a happy child. She loved dressing up and dancing.

Her 7-year-old brother Orayln Thomas was a bit more reserved. He went by “Ray Ray” and preferred video games to spectacle.

Even so, the two performed at a talent show Friday at the Nenes Kiddie Kollege day-care center in Houston, where they lived.

“They had a great time Friday,” Sophia Faultry, the day care’s director, told WFAA-TV.

The two were probably comfortable onstage at the day care, where they went every day.

“They’re with us on a daily basis,” Faultry told the station. “We pick them up in the mornings, and we drop them off in the evening.”

She remembers sending the young siblings on their way after the show.

“We told the bus driver, ‘We’ll see you Monday,'” she said.

But she wouldn’t.

On Sunday, the two young children’s bodies were discovered in the crawlspace underneath the house next door to where they lived.

The same day, their 30-year-old mother, Sheborah Thomas, was arrested and charged with capital murder for allegedly drowning both children in a bathtub Friday — some hours after the talent show — before hiding their corpses under the house.

Houston police spokeswoman Kese Smith told the Associated Press it appears that Thomas first attempted to bury the two bodies but eventually placed them under the house when that was too difficult.

Thomas was charged after an unnamed acquaintance found her throwing mounds of trash into a nearby field. When he asked her what she was doing, she said she needed to move from her house immediately. She asked him to help her pack, to which he agreed.

She also allegedly told him that she had killed her children.

He thought it was a twisted joke, a bit of dark humor.

“She was so matter of fact about it he didn’t think she was serious. He thought she was joking,” Smith told the Associated Press. “He continued to help her pack.”

It dawned on the man that Thomas might be telling the truth after he asked about her children again, only to receive the same answer. He persuaded her to get in his car, then immediately took drove her to a police station.

As of early Monday morning, there was not a clear motive for the killing. Thomas does not have a known history of mental illness. She does have a minor criminal history, but police could not offer more details, ABC 13 reported.

Tejal Patel, a Houston spokeswoman for the Texas Department of Family and Protective Services, said that representatives from her office had visited the family in the past, but she couldn’t offer further details as to the nature of the visit.

“Obviously we want to know how this happened, why this happened,” Patel told the Houston Chronicle. “We just feel horrible. This is just a tragic case.”

The news shocked many who knew Thomas.

“She made sure she kept the kids clean,” Thomas’s neighbor Shirley Baines told WFAA. “She takes care of them. She goes to the store. … To me she was, like, a real nice person. They are good kids. They don’t play with nobody. I mean, why would someone do their kids like that? I mean why? They are innocent!”

Other neighbors agreed.

“I never would have thought she would do that. She didn’t seem like the type. She was always with a smile and friendly,” Dee Davis told the Houston Chronicle. “How in the hell can she do something like this? You bring life into the world; it’s not up to you to take it out. I can’t get over this.”

Geovanna Brewer, another neighbor, remembered the kids as joyful.

“I remember when they first moved in — the kids were happy and everything,” Brewer told the newspaper. “It’s like a shocker to me.”

Still, none of the neighbors knew her well. She had moved into the house only three months prior, her landlord George Shoupe told the Houston Chronicle.

Perhaps most shocked was Kita Thomas-Smith, the children’s aunt who broke down crying in an emotional interview with WFAA.

“Why would she do this? Why would anybody do this to their kids?” Thomas-Smith said between sobs.

A GoFundMe campaign has been set up by Thomas-Smith to pay for the funeral services. As of early Monday morning, it had raised $390 of its $10,000 goal.

Thomas also has a 12-year-old son, but he was staying with his father and is safe, according to ABC 13.

As of early Monday morning, it is unclear whether Thomas has an attorney or whether she has entered a plea. She is expected in court Monday, ABC 13 reported.