VEHICLE WAS PARKED ON SLIGHT INCLINE IN DRIVEWAY (NOT RUNNING). KEY WAS IN IGNITION, BUT VEHICLE WAS NOT RUNNING AND IT WAS IN THE OFF POSITION. FOUR YEAR OLD CHILD SHIFTED VEHICLE OUT OF PARK INTO NEUTRAL CAUSING IT TO ROLL DOWN A HILL AND IMPACT SEVERAL TREES (NO INJURIES). AFTER THE INCIDENT, WE HAVE FOUND THAT THE VEHICLE CAN OCCASIONALLY BE EASILY SHIFTED OUT OF PARK WITH NO KEY IN THE IGNITION AND WITHOUT APPLYING PRESSURE TO THE BRAKE PEDAL. MOST OF THE TIME IT FUNCTIONS AS IT SUPPOSED TO (AND WON'T LET YOU TAKE IT OUT OF PARK).