The incident took place around noon, on Sunday, Jan. 30 in the parking lot of Southampton Youth Services, said Lt. Susan Ralph, of the Southampton Town Police.
According to Ralph, the child had been sledding, when the relative started the 2007 Jeep in the parking lot and began loading the vehicle when it began to roll forward and then struck the child.
The vehicle continued to roll despite the owner's attempt to stop it and after hitting the child, struck a Southampton Town Highway vehicle plowing the lot, Ralph said.
Southampton Town Patrol Units and Southampton Volunteer Ambulance responded to render aid to the child.
The child was airlifted to Stony Brook Hospital by Suffolk County Aviation Unit for treatment.
The Southampton Town Detective Division responded to investigate the cause of the accident.
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