An infant is at Wolfson Children's Hospital in downtown Jacksonville Tuesday night in critical condition after a 65-year-old babysitter grew frustrated and threw the baby, authorities say.

The 5-month-old boy was in the care of Barbara Kendrick, an acquaintance of the baby's parents who were at work Tuesday morning when the infant was in Kendrick's care. They'd been leaving the baby in Kendrick's care for just over a month, says Sergeant Jay Farhat with the Jacksonville Sheriff's Office.

Kendrick is charged with aggravated child abuse, Farhat says.

She called 911 around 2:15 p.m. after going to a neighbor for help. Originally, the child was rushed to UF Health with injuries that were life-threatening and visible trauma.

"The prognosis is not good," Farhat says.

Investigators brought Kendrick into their headquarters for questioning. She dodged the questions at first, but Farhat says she eventually admitted she threw the baby. Farhat says he doesn't want to get into specifics, but believes she became frustrated with the baby's fussing.

Kendrick lives in Oceanway on the 220 block of Davis Street. She had no other criminal issues, police say.

This is a developing story. Stay with First Coast News for updates.