A two-year-old boy has fatally shot his mother from the back seat of the car she was driving along a Milwaukee highway, relatives said.
Antonio Price said investigators told him that his sister Patrice was driving with her two sons, aged one and two, riding in the back seat on Tuesday when she was shot.
Mr Price said authorities told him the older boy fired the gun. He added that his mother was in the passenger seat and was not struck.
Milwaukee County sheriff's department said in a statement that a 26-year-old woman was shot once in the back while driving on Highway 175 about 10.30am on Tuesday and that the shooter appeared to have been a child in the back seat.
The department did not identify the woman nor explain the relationship between her and the child.
First responders attempted CPR, but the woman was pronounced dead at the scene, officials said.
Mr Price, 28, described his sister as gracious.
He said: "She was the best mom for her kids, put clothes on their back. When I needed her, she always cared for me and gave me great advice."
Ms Price's 50-year-old father, Andre, said she was driving her boyfriend's car when she was shot.
He described her as a hardworking mother of three and said she had a daughter aged seven or eight.
Last month Jamie Gilt, 31, was shot in the back by her four-year-old son in Florida using a handgun that slid from underneath the front seat to the back where he was seated. Ms Gilt survived the shooting.
Putnam County sheriff's officials said the boy had recently learned how to unbuckle himself.
He climbed out of his seat, picked up the gun and fired through the front seat, hitting his mother in the back, investigators said.