York regional police say the four-vehicle crash in King Township happened on the morning of Aug. 4., and involved nine people.
Officers determined a Volvo had crashed into a Ford Taurus, which then struck a Chevrolet Cobalt before colliding head-on with a Honda Civic.
Five people in the Civic — including the driver, his wife, their 11-year-old boy, five-year-old girl and three-year-old boy — were taken to hospital with serious injuries.
Police say the girl died five days later.
The Volvo driver, Kamau Davis-Locke of Newmarket, has been charged following a “lengthy and thorough” investigation.
He faces 12 charges that include impaired driving causing death and criminal negligence causing death.