Two of the children - a 10-year-old boy and an 11-year-old girl - were struck by bullets Wednesday night. The two were taken to a hospital with non-life-threatening injuries and remained hospitalized Thursday.
The Milwaukee Journal Sentinel reports the children were taken to the hospital only after the driver was dropped off and the mother got behind the wheel.
Milwaukee Police Chief Edward Flynn says the mother had recently received all seven children, ages 2 to 11, back into her custody after allegations of child abuse. The children have now been referred back to child welfare officials.
The driver was taken into custody on a probation violation.