Grandfather fought in WWII for 6 yrs, dropped out of school: Musk

Billionaire Elon Musk said his grandfather fought in World War II for six years and suffered from "severe PTSD". He said his grandfather dropped out of high school but scored high in an IQ test taken towards the war's end. Due to this, he was sent to work for British Intelligence, else "he'd probably be dead and I wouldn't exist".