Joan Leslie was born in Detroit and began acting as a child performer. She was never able to escape the good girl role in her early work. She married Dr. William Caldwell in 1950. She quit her acting career to raise her identical twin daughters Patrice and Ellen. Both daughters are now Doctors teaching at universities.
Performed under her real name, debuting in Camille, until adopting "Joan Leslie" for High Sierra. Her sister, Mary Brodel, had a short career in the 1940s, as did her other sister, Betty Brodel.