Officers say the crash happened just before 7:50 p.m. on Monday in the 100 block of Delaware Drive, in the Collins Park neighborhood of New Castle.
Surveillance footage captured a white pickup truck, possibly a GMC or Chevrolet with an extended bed.
New Castle County police released pictures of the suspect and his vehicle.
Action News has been told the driver stopped after hitting the child, got out of the car and then drove off with another passenger inside.
The child was treated for minor injuries and released from the hospital.
If you recognize this individual or have any information regarding this investigation, contact Officer Felix-Bermudez at Fernando.Felix-Bermudez@newcastlede.gov or call the New Castle County Division of Police non-emergency line at (302) 573-2800.