01/18/2013 02:31 pm ET

Tina Alberson Trial: Jonathan James' Twin Brother Testifies He Wanted Water Before Death

The fate of a woman accused of killing her stepson by denying him water for days is now in the hands of a Dallas jury, NBC's Dallas-Forth Worth station reported.

Tina Alberson has admitted that she punished Jonathan James, 10, by not allowing him to drink water on limited occasions, the Dallas Morning News reported.

The jury began deliberations on Friday.

During her testimony Thursday, she said that he wasn't completely cut off.

"I would lay down my life for those kids," she said about James. He and his twin brother were staying with her and their father for a month.

But prosecutors allege that's untrue. A medical examiner found that there was no urine in his bladder when he died from dehydration on July 25, 2011, according to KDFW.

Prosecutors have portrayed Alberson as a strict disciplinarian who forced James to stand in place for long periods of time in the scorching heat without allowing him to drink. She sometimes made the child hold a sack of potatoes above his head. For days, they allege, James was punished for wetting the bed and taking his brother's guitar strings.

Alberson, who faces life imprisonment if convicted of felony injury to a child, also testified that James didn't appear to be in any danger, the Associated Press said.

James' fraternal twin brother Joseph, however, told a different story when he took the stand on Thursday.

"He would be asking for water and she would say no because he was in trouble," Joseph said, according to KVUE.

Joseph, now 12, swore that his brother pretended he needed to use the toilet so he could cup his hands under running water in the sink.

Eventually, Jonathan collapsed and was placed in a tub.

"He didn't look like the normal kid that I knew," he said, according to CBS' station.

Michael Ray James has also testified against his wife, saying that he blames her for his son's death. He has severe medical problems and is legally blind and testified that he was unaware of the boy's distress in the days leading up to his demise. He faces the same charges however and will stand trial next.