When he was fourteen, Corky and his family moved from a small Missouri town to Chula Vista, California. Corky started a small construction company in Bonita, California in 1960, with his wife, Vonnie, who handled accounting duties. While McMillin was busy building houses, his passion was taking his family to the Imperial Sand Dunes on the weekends. As sons Mark and Scott got older, McMillin decided to try his hand at off-road racing. His first venture into a competitive event came at the 1976 Baja 1000 with his son, Mark. Although the father-son team did not finish that first race, Corky kept after it and his first win came in the 1979 Baja 1000. McMillin went on to win many more races including the San Felipe 250, Baja 500, Baja 1000, Parker 400, and Fireworks 250, most of them multiple times. Over the years, McMillin won three SCORE Points Championships and on two occasions won overall titles at both the San Felipe 250 and the Baja 500. As the McMillin Companies continued to prosper, Corky expanded into different markets, including Liberty Station, a conversion project on the site of the former San Diego Naval Training Center. He eventually became one of the largest private developers in the country. The Corky McMillin Companies donated $1.5 million to enhance the real estate program at San Diego State University's College of Business Administration. In the Poway Unified School District, McMillin contributed to anti-drug programs through Partners in Education. Corky McMillin died at the age of 76 less than two weeks after he had a heart attack while racing in his final desert race, the SCORE Las VegasPrimm 300. He has eight grand children. In 2000, because of his contributions to the community, an elementary school in Chula Vista was named after him. Vonnie McMillin died August 30, 2016, after an extended battle with Parkinsons disease. While his sons continue to run the family business — The Corky McMillin Companies — his daughter, Laurie Ann, an interior designer who is also on the board of directors of the family's corporation, decorates the company's model homes.