1970-1972: Patty Duke and actor John Astin engage in affair and later wed Duke and The Addams Family star had a romantic affair while he was still married. When Duke became pregnant with Sean in 1970, she wasn’t certain who the father was — she had been seeing actor and musician Desi Arnaz Jr., as well as Addams Family star John.
John Astin Patty Duke
"There was a lot of stuff in the press early on," John Astin told PEOPLE in 2001 of his son Sean's birth. When Patty Duke gave birth to her first son, Sean Astin, in 1971, her life.