Dec. 31, 2010 -- Mona Nelson, the woman charged with killing 12-year-old Jonathan Foster and burning his body, defended herself against gruesome allegations by arguing that she is a grandmother who loves kids.
"I'm not a monster," she told ABC affiliate KTRK.
"I have five grand kids and I love kids," Nelson said.
Nelson, the mother of 26-year-old twins, has been charged with capital murder and is being held without bond in Harris County Jail in Houston, Texas. Jonathan's body was identified after he vanished on Christmas Eve. His body was so badly burned that he had to be identified using his dental records.
Investigators are not impressed with Nelson's plea that she is not a monster.
"She is a cold, soulless murderer who showed an absolute lack of remorse in taking the life of Jonathan Foster," Houston Police Offer Mike Miller said told a press conference Thursday. "There's only been one or two people I've ever talked to that had eyes like she did; it was pretty cold."
Miller also believes that Jonathan may not be Nelson's first victim.
"Do I believe she's done it before? Yeah, I do. I don't believe she began and ended with the abduction of Jonathan Foster, I don't," Miller said.
Houston Police Department spokesman Kese Smith said, "We believe she acted alone."
From jail, Nelson, 44, defended herself, saying that she was approached by Jonathan's family on Christmas Eve.
Nelson claims that they she knew Jonathan's family and that they stopped by her home and asked her to dump a plastic container in exchange for $20. She said that she was drunk on vodka and never looked to see what was inside the container when she dropped it into a ditch in northeast Houston.
"I didn't know what was in it until they were showing me pictures in the interrogation room," Nelson told KTRK.
Child Killer Suspect Mona Nelson Is Former Boxer, Welder
Investigators don't believe Nelson's story. Jonathan's body wasn't found in a plastic container. Police believe Nelson acted on her own and that Jonathan was killed on Christmas Eve, the same day he disappeared.
Nelson is a former boxer who currently works as a maintenance worker and a welder.
Nelson boxed professionally in 2004, winning one match and losing three. During her brief stint as a boxer, she was suspended for 30 days by the Association of Boxing Commissions. The record does not state why Nelson was suspended.
Burned carpet and twine that may have been used to tie the young boy's hands were found in Nelson's apartment. Nelson's welding equipment was also found at her apartment. Police think the welding equipment may have been used to burn the fifth grader's body.
"Once we arrived at her [Nelson's] house, we stumbled into a wealth of evidence, evidence that showed perhaps his body was burned at the residence, evidence that showed the items he was burned with, evidence that had us pretty shaken up in collecting it," Miller said.
Nelson admitted to being a welder, but not to being a murderer.
"I do have a cutting torch. I'm a welder. I would never do that," Nelson told KTRK.
Nelson's sister defended her saying that she spent Christmas day with her.
"She showed no signs of doing anything to anybody illegal," Angie Johnson, Nelson's sister, told the station. "I don't believe at all she has anything to do with killing a child. That's not Mona."
But Houston Police believe she did kill Jonathan.
"She decided when the time was right and she swooped down and took him when she saw the time was right and she saw an opportune moment," Miller said.
Nelson has a criminal history that includes charges of aggravated robbery, drug charges and threatening a woman.
A next door neighbor of Jonathan's mother, Angela Davis, told KTRK that Nelson was with the family when they were looking for the missing boy on Christmas Eve.
"She [Nelson] was just sitting there, looking at what was going on," Rita Jackson told KTRK.
Houston Police wouldn't comment on the neighbor's claims.
Smith described Nelson as an "acquaintance" of Jonathan's family. "She knew [Jonathan's] mother's roommate and she was a former maintenance worker at the apartment complex," Smith said.
Nelson is also believed to be the woman who Jonathan's mother claims answered the phone at her home on Christmas Eve, a chilling call that had authorities concerned for Foster's safety.
Smith said that Houston police are still investigating the phone call.
Did Jonathan's Family Know Mona Nelson?
Mary Gifford, the boy's grandmother, said that when her daughter called her son on Friday, a woman she did not know picked up the phone.
"My daughter asked to speak with her son, and then the woman asked [Jonathan] if Angela was his mother," said Gifford. "He said, 'Yes ma'am, Angela is my mother,' and then the phone went dead."
Gifford, who had been holding out hope that her grandson would be found alive, told ABCNews.com earlier this week that she's devastated over his death.
"I'm trying to hang in there, but what would be going through your mind if this happened to your child?" she said. "I keep thinking 'Why did she do it? Did she torture him? Why didn't she just let him come home?"
Glenn Scrimsher, Jonathan's uncle who had cared for the boy for four years until November 2009 when he went to live with his grandmother, said today that he had always worried about his nephew living with his mother.
"I was worried," said Scrimsher. "Because of my sister's state of mind and her lifestyle was not that of a caring mother who looks after her children."
Scrimsher said he didn't know Jonathan was living with his mother until after the fact. Foster moved back in with Davis just last month.
"The last time I saw him was the day he was leaving for his grandmother's," said Scrimsher. "He was happy to see his grandmother. He called her his granny."
"He loved her very much and he missed her," Scrimsher said.
Gifford, has said that she believed the Houston police waited too long to issue an Amber Alert for the missing boy. The alert was issued on Monday afternoon, nearly three days since he had last been seen.
"Regardless of how this turns out, my goal is to get the Amber Alert law changed," she said. "There should not be criteria for an Amber Alert that depends on whether cops think the kid has run away."
"The cops kept thinking [Jonathan] ran away," she said. "But he had waited too many years to go back with his mama, that's what he wished for on his birthdays, to be back with his mama... That doesn't sound like a kid who wants to run."
Police spokesman Smith defended the timing of the Amber Alert, saying that conflicting accounts of what happened the day Jonathan went missing made the case even harder for investigators.
While he wouldn't specify what the conflicting stories were about in great detail, Smith said that the mother and the boy's stepfather David Davis had originally said that Jonathan was home with a babysitter when he disappeared, but later said he had been at home alone.
ABC Affiliate KTRK contributed to this report.