A woman sentenced to death in the killings of two children lost her petition to the United States Supreme Court.

The high court will not hear the case of Heather Leavell-Keaton, who was convicted for the murder of 3-year-old Chase DeBlase and manslaughter in the death of 4-year-old Natalie DeBlase. She wanted to appeal the sentence because attorneys said she could not show good behavior evidence since she had been in prison.

Prosecutors believe Leavell-Keaton poisoned the siblings with anti-freeze. They also said there is evidence their father, Leavell-Keaton's boyfriend, strangled them.

In 2015, Leavell-Keaton was sentenced to death. However, she was given a second sentencing hearing after her attorneys said she could not speak at her original sentencing hearing. The second sentencing also ended in the death penalty.

The children's father, John DeBlase, was also sentenced to death.

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