WAS TRAVELING ABOUT 20 MPH IN MY 2003 MERCURY MARAUDER AND WAS HIT FROM BEHIND AT ~45 - 50 MPH. DURING THE IMPACT THE DRIVER'S SEAT BACK FAILED AND FELL BACKWARDS. LUCKILY MY DAUGHTER (5 YRS OLD) WAS NOT IN THE BOOSTER SEAT THAT IS DIRECTLY BEHIND ME. IF SHE HAD BEEN WITH ME, SHE MOST CERTAINLY WOULD HAVE HAD SERIOUS INJURIES. WHEN THE SEAT FELL BACK, MY INSTINCT WAS TO TRY TO STAY UPRIGHT. THIS CAUSED SIGNIFICANT NECK STRAIN. WHEN I THEN CAME INTO CONTACT WITH THE VEHICLE IN FRONT OF ME, I SLID UNDER THE SEAT BELT AND MY KNEE MADE HARD CONTACT WITH THE DASH. *JS