A 9-month-old baby has died in Florida after his mother put fentanyl in his bottle for a nap, Nassau County Sheriff Bill Leeper said.

“Officers received a call Monday about a baby who was not breathing and had no pulse, they tried to CPR the baby until firefighters took him to a Jacksonville hospital, where he was pronounced dead,” Leeper said.

The 17-year-old mother allegedly “changed her story several times,” “At first, the mother said she didn’t know what happened. She put the baby to sleep and couldn’t wake him up,” but ultimately “confessed” that she was Tired and wanting a nap, she filled the baby’s bottle, and put some “what she thought was cocaine” in the bottle to put him to sleep, the sheriff said.

The medical examiner’s office said the boy had about 10 times more fentanyl in his bloodstream than a fatal dose, and determined the cause of death was an overdose of the same drug.

“The suspect knowingly performed an act that she should have known, or should have known, would cause death or serious bodily injury to her child. Who does that? What mother would do that? It’s not normal. It’s sick. It’s beyond my imagination that a mother would do that to her son. Leeper said.

There were other people in the house at the time of the incident, but investigators believe it was solely the mother’s decisions that caused the baby’s death. Authorities have not released the names of the mother or her son. She has been charged with aggravated murder and possession of an illegal substance.

Sheriff’s deputies and the Florida Department of Children and Families continue to investigate the facts.

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