Patty Duke married her first husband Harry Falk, who was 13 years older, in 1965 when she was 18-years-old. The couple divorced in 1970.
She had relationships with Desi Arnaz Jr., John Astin and rock promoter Michael Tell around the same time. She married Tell on June 26, 1970, after learning she was pregnant, though the paternity of her child was unclear. It was a marriage that lasted just 13 days. Her son, Sean Astin, was born Feb. 25, 1917. DNA testing in 1994 proved that Sean Astin was Tell's son.
Duke's third husband became John Astin and together they had a son named Mackenzie. For a time the actress was known as Patty Duke Astin.
Her fourth and final marriage was to drill sergeant Michael Pearce in 1986. Pearce had served as a consultant to a film Duke worked on, "A Time to Triumph."
Eighteen-year-old Patty Duke poses with her fiance, television director Harry G. Falk, 32, Oct. 1965.