Larson was reared on a family farm at Thousand Oaks and Jones-Maltsberger Road; the location is now heavily urbanized. When his parents divorced, he lived with his father, a large-animal veterinarian. He has a twin sister and a total of four siblings. His sisters went to live with their mother when the parents' marriage ended, and he was hence separated from his twin. While working on the farm, Larson contracted paratyphoid from handling feed for hogs and not washing his hands before eating. He lost weight and remained thin