Transcript for Prosecutors Say Mom Poured Salt Down Foster Son's Throat
Reporter: Hannah Overton says she loved her 4-year-old Andrew burd, but prosecutors believe she fatally poisoned the young boy with a cajun spice and water. Reporter: News of Andrew's bizarre death by salt poisoning hit the Texas gulf coast like a hurricane. Overnight, Hannah and Larry Overton's quiet life was shattered. It's somebody's worst nightmare. After your child dies to be told that somebody thinks it's your fault. We were just waiting for someone to look at it and say this is just an accident. Reporter: And instead? Instead we were arrested. Reporter: To investigators, Andrew burd's death was no accident. The authorities quickly began weaving a sinister tale of murder, a pregnant mother of four who became overwhelmed with the arrival of a foster child. Former nueces county prosecutor, Sandra Eastwood. Andrew had an enraged mother who didn't -- I don't think, love him the way that she loved her own biological children. Reporter: The prosecution's theory was that Hannah turned abusive, ultimately forcing him to consume a toxic dose of this creole seasoning. Detectives even used the overtons' own children to build a case against them. Investigators believed these interviews with an 8-year-old Isaac, obtained exclusively by "20/20," seem to prove there were unusual forms of punishment. You get pepper? What does that mean? It's like spicy and it hurts your mouth. We have a security camera that's facing his bed. Every night my mom watches it until we see him fall asleep. Why? To make sure he doesn't do bad things. It's a little odd. You adopt a child and you watch the child through a security camera because he's always in the bed. All these things started like adding up, like pieces in a puzzle. Reporter: The odd circumstances found at the Overton home were detailed in these arrest warrants, describing a virtual torture chamber. This case boils down to a woman who tortured a child, making him sleep on rough plywood. Burning sheets, becoming so enraged she forced him to have 23 teaspoons of hot pepper, and then watching him die in agony. For 2 1/2 hours. Reporter: A grand jury charged both Hannah and Larry Overton with killing Andrew burd, capital murder, an automatic life sentence in Texas because Andrew was under the age of 6. But the Overton's church community, led by pastor rod carver and his wife Noreen, saw the accusations as ludicrous. The church even raised $700,000 for their defense. It's so bizarre because she's really the last person you would think would be charged with this type of crime. Reporter: While Hannah and Larry awaited separate trials, Hannah gave birth to a baby girl, Emma. But child welfare placed all five children with loved ones, allowing the couple only supervised visits. From day one of Hannah's trial, prosecutors attacked Hannah's seemingly calm, motherly demeanor and made her out to be an abusive monster. A comment someone made was that it appeared that this child had been in a fight with a porcupine. I remember some kind of injury that was there, either bruising on the elbows or knees. Reporter: And there was more damning testimony. This time from Andrew's foster mother before he lived with the overtons, Sharon Hamil. Andrew was not a difficult child to take care of. At least he was not when he was with me. I used to keep food and things on the table, and I never had Andrew take anything off of the table and hide it or eat it. Reporter: But Hannah told the jury the exact opposite. We did have problems with him. He had a real obsession with eating. And when meal time was over, it almost always ended in tears. Reporter: Hannah and Larry say they first tried giving Andrew as much as he wanted to eat, and his appetite was often startling. I think I made him a dozen-and-a-half eggs. And a bunch of bacon. And he would eat -- he ate to the point where he threw up. Reporter: He ate a dozen-and-a-half eggs? After he had thrown up. We'd say, you're too full, you're throwing up. That's why. You don't have room in your tummy. That's why it's coming back out. Reporter: The defense introduced a medical mystery suggesting Andrew might have pica, a strange eating disorder marked by an obsessive appetite, sometimes for things that aren't even edible. According to the overtons, in one sitting, Andrew would eat five bananas or an entire jar of pickles. And people outside the home also witnessed Andrew's bizarre eating. Christina Velazquez, his Sunday school teacher at the time, says she had to move the trash can away from Andrew. When it came time for craft, he would try to eat the glue, he would try to get things out of the trash and put it in his mouth. Reporter: And, she told the jury, the marks on his body may have been self-inflicted. He was always picking at his scabs. And if he had a little bug bite, he would scratch it so much that it would start to bleed. Reporter: And what about the odd circumstances in the overtons' house? The camera pointed at his bed, for instance? Hannah says it was just her way of coping after a family car crash which put the pregnant mother of five on bedrest. Hannah says the child video monitor helped her make sure Andrew was safe, while she was recovering from her injuries. His eating problems escalated, just everything just got ten times worse. Reporter: And Andrew's behavior the day before he died, say the overtons, became even more disturbing. It started as another tantrum. When he was put in his room, he got really upset and he pooped on himself, and he got the poop and he was smearing it. He smeared it all over the wall and all over the sheets, and it got all over the mattress. It was all over the place. Reporter: Which is why Hannah and Larry say the mattress was outside and the spiderman sheets were burned. It wasn't an act of cruelty, as the prosecution suggested. It was just a clumsy attempt to clean up feces that Andrew had smeared everywhere. My husband had put the sheets in a bag and put them in the trash because they were so soiled. And I know that Andrew kept coming in and trying to get the sheets out of the trash can. I knew there was another set to replace them with and so my solution, in my frustration, was just to burn them. Reporter: Hannah said Andrew slept on their bedroom floor that night in a sleeping bag. The next day, the day Andrew died, Hannah says she gave him the water with Zatarain's, not to punish him, but to soothe his appetite. Could it be that you held his nose, held his neck, and made him drink this horrible concoction? Absolutely not. Reporter: Did you force feed him salt? Absolutely not. Reporter: Did you force feed him Zatarain's? No. It just doesn't make sense. Reporter: Hannah's trial attorney Chris Pinedo. The prosecutor said in that Hannah was holding the child by the throat, and pouring the salt down. How many hands does she have, to hold his mouth open, hold him by the throat and yet pour it down? It's just not going to happen. Reporter: But what about the idea of pepper flakes as punishment? Hannah says the prosecution got it all wrong. A very different situation, a long time ago we had a pastor that suggested that you get that pizza hut pizza flakes and put one on their tongue. They weren't forced to ever eat it. You stick your tongue out, like that, and take it off. It's a very quick reminder that we can hurt others with our tongue. Reporter: But if Andrew wasn't punished with seasoning, where did the salt come from? Hannah says she's still haunted by something she might have missed that day while recovering from the car accident. I had taken a tylenol with codeine, and I dozed off for a minute. And when I woke up, Andrew wasn't there, so I went to go see where he was, and he was in the pantry. He was trying to get into something on one of the top shelves. I think that it was either the salt or the pepper, but I'm not really sure exactly. Reporter: With Hannah facing life in prison, which version of events would the jury believe? We the jury, find the defendant -- Reporter: That's next.
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