Police said the boy was playing with a gun in front of his sister just before 2:30 a.m. when it went off. The girl was taken to Jamaica Hospital with non-life threatening injuries and is in stable condition.
The boy will be charged in family court with criminal possession of a weapon. According to police, the boy first told them he found the .22-caliber Colt revolver in the street, then said he got it from a friend.
Detectives said the gun is the same caliber as the weapon used in the fatal shooting of Mohammed Hamwi, a 48-year-old IT specialist, in the same Queens neighborhood earlier this week. The weapon used in that crime was never recovered.
Police will test the gun to determine if it was involved in both incidents.
The boy is currently suspended from school for a previous matter. He was charged as a juvenile with trespassing and police had been previously called to his home for other disputes.
The children's 41-year-old mother, her boyfriend, a 5-year-old boy and three family friends were in the house at the time of the shooting. The mother has not being charged.