REAR WINDOW WAS ROLLED DOWN WHILE 2 1/2 YEAR OLD CHILD HAD HIS ARM AGAINST THE INTERIOR DOOR, WHERE IT MEETS THE BOTTOM OF THE WINDOW. THE SKIN OF THE CHILD'S FOREARM WAS SUCKED INTO THE VEHICLE'S DOOR. CHILD WAS TRAPPED UNTIL WINDOW WAS ROLLED BACK UP. BRUISING OCCURRED BUT THE SKIN WAS NOT BROKEN. VEHICLE WAS STATIONARY AND PARKED IN A LOT.