Abstract: A head support apparatus for use with child car seats to prevent a child's head from loosely swinging forward and side to side as a result of the movement of a vehicle, particularly when the child is asleep. In a preferred configuration, the apparatus comprises a head device that is received on or around the head of the child, a harness assembly that attaches the apparatus to the car seat and an attachment mechanism that removably attaches the head device to the harness assembly. Preferably, the head device is a cap, beanie, headband or other hat-like object. The preferred harness assembly has a pair of longitudinal straps that are received through slots in the back wall of the car seat body and a lateral strap that is movably engaged with the longitudinal straps and configured to attach to the head device. The attachment mechanism can be a hook-and-loop connector.