A boy aged five was knocked over by a car on Hove seafront.
The young pedestrian suffered head injuries in the accident on the A259.
He was taken to the Royal Sussex County Hospital, Brighton, just before 1pm on Thursday 29 October and was kept in overnight.
The accident happened at the junction of Kingsway and Langdale Gardens.
Sussex Police want any witnesses to call the Road Policing Unit at Hove on 0845 6070999.