VEHICLE STRUCK FROM BEHIND AND PUSHED INTO TRAFFIC SUSTAINING REAR, FRONT AND SIDE COLLISIONS. ONLY PASSENGER SIDE CURTAIN AIRBAG INFLATED, NO OTHER AIRBAGS INFLATED. ALSO BOTH DRIVER AND PASSENGER SEAT BACKS FAILED RESULTING IN FATAL INJURIES TO DRIVER AND SERIOUS INJURIES TO PASSENGER. THE VEHICLE WAS STATIONARY OR JUST STARTED MOVING WHEN IT WAS STRUCK FROM BEHIND ON HIGHWAY AND PUSHED INTO OTHER LANES OF TRAFFIC.