AUBURN, Wash. (AP) — Auburn police say a shooting last week that left a 15-year-old girl in critical condition has been ruled an accident.

Police responded to the incident last Friday around 7:30 p.m. An Auburn Police commander said the girl’s 13-year-old brother was playing with a gun he thought was unloaded, and accidentally shot his older sister.

Paula Horstead, the children’s grandmother, said the family is heartbroken. Horstead said as of Tuesday the child was in an induced coma after receiving surgery.