An 8-year-old boy accidently shot and killed his 2-year-old sister inside their California home, KTVU.com reported.
The girl was shot once in the head and officials told the station she was unresponsive when the Vacaville Fire Department's paramedics arrived.
Lt. Craig Courtemanche told KTVU her parents and brother were inside the house at the time.
She was pronounced dead at Vaca Valley Hospital.
Authorities are investigating, but police believe the incident was accidental.