A 16-month-old Tustin girl was killed Sunday afternoon when a family friend backed out of a driveway and struck the child, a police spokesman said.
Tustin Police Lt. Charles Crane said the name of the child, who died of massive head injuries at Western Medical Center in Santa Ana, would not be released until the investigation was completed.
He also declined to identify the driver of the vehicle.
"All I can say is that the driver was not related. He was a friend of the family," Crane said.
The girl was treated at the scene by paramedics after the 1:50 p.m. accident.
She was rushed to the medical center and placed on a life-support system but died at 4:30 p.m., Crane said.
The coroner's office has scheduled an autopsy, a spokesman said.