I WAS DRIVING ON HIGHWAY 101 IN CALIFORNIA IN MODERATE TRAFFIC WHEN THERE WAS AN UNEXPECTED SLOWDOWN. I BRAKED IN TIME, BUT THE VEHICLE BEHIND ME DID NOT. I WAS REAR-ENDED AND MY CAR WAS TOTALED. I WAS NOT INJURED. HOWEVER, THE PERSON IN THE PASSENGER SEAT, WHO WAS WEARING HER SEAT BELT, WAS THROWN FORWARD. SHE STRUCK HER HEAD ON THE DASHBOARD (POSSIBLY THE GRILL) AND INCURRED A SERIOUS EYE INJURY THAT REQUIRED SURGERY TO REPAIR. I AM REPORTING THIS BECAUSE ALTHOUGH THE LAP PORTION OF THE SEAT BELT RESTRAINED HER, APPARENTLY THE SHOULDER PORTION DID NOT. THE ACCIDENT IS DOCUMENTED IN TRAFFIC COLLISION REPORT #9360-2020-00053 ISSUED BY THE CALIFORNIA HIGHWAY PATROL, 6100 LABATH AVE., ROHNERT PARK, CA. 707-588-1400. THE PHOTO I'VE ATTACHED WAS TAKEN ABOUT THREE DAYS AFTER THE ACCIDENT.