An Alabama woman will die for the 2010 poisoning murder of her common-law husband's 3-year-old son.

Mobile County Circuit Court judge Roderick Stout on Thursday sentenced Heather Leavell-Keaton to death by lethal injection, upholding jurors' recommendation.

AL.com reports Leavell-Keaton is the first woman in Mobile County history sentenced to death row.

Sentenced to die: Heather Leavell-Keaton was sentenced to death by lethal injection in Alabama on Thursday

Sick: Prosecutors have also said that Leavell-Keaton killed Natalie DeBlase out of jealousy for the way she was treated like 'a princess' by some members of family. Prosecutors have said the children were tortured, gagged and choked to death

The jury found that Leavell-Keaton intentionally killed Chase DeBlase in 2010, and recklessly caused the death of his 4-year-old sister Natalie DeBlase, whose body was found dumped in a wooded area near Cintronelle, Alabama.

Prosecutors alleged that Leavell-Keaton cooked anti-freeze into the children's food.

Their father, John DeBlase, was sentenced to die in late 2014 after being convicted on multiple counts of capital murder.

Two jurors from the John DeBlase trial and five jurors from the Leavell-Keaton trial attended the hearing.

Prosecutors have said the children were tortured, gagged and choked to death. Chase and Natalie DeBlase's bodies were found dumped in remote areas near Citronelle, Alabama, and Vancleave, Mississippi.

Prosecutors have also said that Leavell-Keaton killed Natalie DeBlase out of jealousy for the way she was treated like 'a princess' by some members of family.

Capital murder: The jury found that Leavell-Keaton intentionally killed Chase DeBlase in 2010, and recklessly caused the death of his 4-year-old sister Natalie DeBlase

The father of the children, John DeBlase, was sentenced to die in late 2014 after being convicted on multiple counts of capital murder

AL.com reports that Chase was subsequently killed after he started asking what had happened to his sister.

He was left taped to a broom handle in the corner of the couple's room overnight before he was found choked to death in the woods outside Vancleave, Mississippi in June 2010, according to witness testimony.

'We believe that Heather Keaton...is a domineering, manipulative, deceitful and morally unhinged woman,' Mobile District Attorney Ashley Rich said prior to the ruling. 'Her actions are worthy of the death penalty.'

However, the doomed killer step-mom's attorney claims his client is a different woman from the one who intentionally poisoned a child to death.

Greg Hughes argued Leavell-Keaton should have been spared the needle because she's become 'a spiritual person now.'

'She's into reading the Bible and writing songs and poems and she keeps to herself,' Hughes said. 'She's not going to be someone causing problems.'

He also added that Leavell-Keaton grew up in a dysfunctional family, developed bipolar disorder at a young age, and lived with a partial blindness throughout her life.