He was first married to actress Pati Behrs, née Pati Behrs Eristoff (February 13, 1922 - July 10, 2004). Pati Behrs was a Russian-born American actress, a grandniece of Leo Tolstoy. She was married to Derek from 1951 to 1957. They had two children, Russell and Sean. Derek took photos of all three of his last wives (at different times) for Playboy magazine.