There are numerous errors in regard to the premise of Grampa's kidneys exploding due to holding in urine too long. 1) Urine is stored in the bladder, not kidneys (kidneys process liquid into urine), so if anything his bladder should have exploded. 2) His bladder or kidneys would not have exploded from holding in urine; all that would have happened would have been that he would just have involuntarily urinated in the car. 3) If Grampa's kidneys did explode, he would die almost immediately from sepsis and internal bleeding, not live long enough to go to the doctor and get X-rays.