LARGO, Fla. — A 17-year-old Largo girl has been charged with child abuse after her 5-week-old son suffered head injuries, Pinellas County deputies said.

We are not naming the mother because of her age.

The investigation began Thursday, when deputies were called about a baby who had been taken to Johns Hopkins All Childrens Hospital on Wednesday night. The baby had a skull fracture and brain bleeding.

Deputies were told the baby had been at home with his mother and twin brother when he was injured. The brother was not injured.

Deputies learned the baby's grandmother had left for work about 6:20 a.m. Wednesday and left the mother alone with her sons. The grandmother checked in throughout the day and no problems were reported.

When the grandmother returned about 4 p.m., she tried to feed the baby, but the boy was lethargic. His head was misshapen.

The grandmother took the baby to the hospital.

Deputies spoke with the baby's mother, who they say provided several stories about what happened and were inconsistent with the injuries.

The baby suffered a fractured skull, a brian hemorrhage and possible brain damage. He remains in the hospital. His brother is also at the hospital until he can be released to foster care.

Friday, detectives interviewed the baby's mother again, and they say she admitted to throwing the child onto the floor out of frustration. She was charged with aggravated child abuse with great bodily harm/permanent disfigurement.

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