From Allan Silverstein:

Poor Bob suffered from "glycogen storage disease" most of his life. You may remember how he could barely run track in PE- for which he was frequently made fun of.- especially by some of male classmates. Well this disease was the reason that he could not run and he suffered from it throughout his life. He had been in a wheelchair for about 10 or 15 year BUT, never complained... and developed very muscular arms- of which he was proud. He was living in south Florida at the time of his death and was soon to enter a memory loss facility. Whether his being run over in an intersection (after darting in with his electric scooter) was somewhat volitional- will never be known.