Stepmother is Sentenced to Death After Cooking Anti-Freeze into Children's Food, Choking Them

Heather Leavell-Keaton, 26, was sentenced to death by lethal injection for her role in the deaths of the 3-year-old boy and 4-year-old girl.

A woman who cooked anti-freeze into food she gave her common-law husband's two young children has been sentenced to death.

An Alabama jury found Heather Leavell-Keaton, 26, guilty of the 2010 murder of three-year-old Chase DeBlase. They ruled that she also recklessly caused the death of his four-year-old sister, Natalie, just months earlier.

On Thursday, Mobile County Circuit Court judge Roderick Stout sentenced Leavell-Keaton to death by lethal injection making her the first woman in the history of the county to be sent to death row.

Read: Police: Mom Killed Her 3 Sons Because Her Husband Paid More Attention to Them Than Her Daughter

She was emotionless throughout the hearing, AL.com reported.

Prosecutors said that, in March 2010, four-year-old Natalie was duct-taped and put in a suitcase that was then left in a closet for 12 hours. She choked to death and her body was dumped in a wooded area in Citronelle, Alabama.

Three months later, when Chase started asking where his sister was, the boy was taped to a broom handle and left in a corner of the couple's bedroom overnight, according to prosecutors. He also choked to death and his body was found in a wooded area in Vancleave, Mississippi.

Leavell-Keaton had also cooked anti-freeze into the children's food, prosecutors said.

Read: 5-Year-Old Boy Crawls Through Wreckage, Calls 911 After Car Crash: 'Mom and Sissy Are Dead'

The children's biological mother sobbed as the details of their deaths were read out in court, AL.com reported.

Prosecutors had claimed that Leavell-Keaton was jealous of the children's mother.

Leavell-Keaton's attorney told the court that she has turned to religion and will no longer be a threat, but the judge still opted for the death penalty.

John DeBlase, the children's father, was sentenced to death in late 2014.

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