A Pennsylvania mother is headed to prison for kidnapping her 6-year-old daughter and taking her to a remote area where she dosed her with opiates and fentanyl because she thought a serial killer — who turned out to be nonexistent — was after them.

Skye Naggy, 32, was sentenced Friday to between 10 and 20 years in prison after she pleaded guilty but mentally ill in January to attempted homicide, aiding suicide, aggravated assault, kidnapping, interference with child custody, and endangering the welfare of a child, the Westmoreland County District Attorney’s Office said in a press release.

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In November 2022, Naggy skipped out on the mental health treatment she was supposed to receive and kidnapped her daughter. She left behind handwritten letters that said she needed opioids to protect herself and her child because she was told by God that she was going to die soon, prosecutors said.

Naggy took the child to a remote area on a trail near Loyalhanna Lake outside of Pittsburgh and made the girl ingest drugs. Police tracked Naggy’s phone and rescued the girl before she died. Officers found a Bible next to them. The girl tested positive for opiates and fentanyl.

Investigators determined Naggy was suffering from schizophrenia. The mother acknowledged her mental health troubles at her sentencing.

“My only goal was to save my daughter from a serial killer,” she said, according to a courtroom report from the Pittsburgh Tribune Review. “I did not realize I had schizophrenia until it was too late. If any unstoppable killer came after you, wouldn’t you make an escape plan? I promise I was just trying to save us.”

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Prosecutors said Naggy will continue to receive treatment while behind bars. The state argued at the sentencing hearing she would be a threat to herself or others should she be released at this time, per the Tribune Review.

Her defense attorneys asked for leniency.

“She has no criminal history and was not involved in the mental health system before this break,” her attorney Wayne McGrew reportedly said. “She should be in a treatment setting and that should be a hospital setting. It is a terrible thing that happened, but mental illness is also a terrible thing.”