CAR WAS STOPPED AND THEN WAS REAR ENDED BY LARGE FORD SUV. UPON INPACT DRIVERS SEAT BACK COLLAPSED INTO BACK SEAT. IF THERE HAD NOT BEEN A BOOK BAG ON REAR SEAT KEEPING IT FROM GOING FLAT SHE WOULD NOT HAVE SEEN SHE WAS PUSHED INTO ONCOMING TRAFFIC AND WAS THEN ABLE TO SWERVE BACK INTO HER LANE. THAT COULD HAVE BEEN A TOTAL LOSS OF CONTROL. ALSO WHILE LAYING FLAT, IF HIT AGAIN SHE WOULD HAVE BEEN SHOT UNDER THE SEAT BELT (AND AIR BAG) POSSIBLY BECOMING SERIOUSLY OR FATALY INJURED.