He described his family as 'conservative, Midwestern, Methodist'.
Through his father's line, Hefner was a descendant of Plymouth governor William Bradford. His mother was of Swedish ancestry, and his father was German and English. He had a younger brother, Keith (1929–2016). Hefner was born in Chicago on April 9, 1926, the first child of Glenn Lucius Hefner (1896–1976), an accountant, and his wife Grace Caroline (Swanson) Hefner (1895–1997) who worked as a teacher.
