Klein married Hilda May Hepner on April 29, 1961. They met at Portage-la-Prairie while Klein was training with the Air Force. As two strong willed individuals there were many difficulties in maintaining their relationship, and after several separations in the late-1960s and early-1970s, Klein and Hilda formally divorced on March 29, 1972 with adultery cited as the grounds for divorce. Hilda received custody of their two children. Klein remarried three months after his divorce to the Victoria-born Colleen Evelyn Hamilton, a single-mother with two children working as an accounting clerk with Imperial Oil and as a bartender by night. They were married in Colleen's mother's basement by Reverend Robert A. Simpson, and together Ralph and Colleen had one child.