How Patty Duke's Son Sean Astin Learned Who His Biological Father Is

When Patty Duke gave birth to her first son, Sean Astin, in 1971, her life was plagued by tabloid headlines.

Duke had colorful romantic history: Having just come out of a scandalous relationship with 17-year-old Desi Arnaz Jr., and impulsively marrying Michael Tell, a “total stranger” who had been subletting her apartment (they were together for 13 days and the marriage was annulled a year later), the media speculated as to who exactly fathered the baby.

The actress ultimately deduced that the father of her baby was actor John Astin, star of the Addams Family TV series, who was married at the time. They kept their affair secret until after their son Sean was born and Astin’s divorce was final, and wed in 1972.

But while Astin raised Sean as his own and had a second child with Duke, the truth about the boy’s paternity wouldn’t come out until years later.

“There was a lot of stuff in the press early on,” Astin told PEOPLE in 2001. “[Sean] basically grew up without any real knowledge of all that stuff.”

When Sean was just 14, Duke confessed that Arnaz was, in fact, Sean’s biological father.

After Sean learned of his paternal background, he began to develop a relationship with Arnaz. But when Sean was nearly 26, he met a relative of Tell’s who suggested they were related.

Determined to discover the truth, Sean underwent a DNA paternal test between himself and all three men.

The outcome: Michael Tell was Sean’s father.

“If you want to know who I am, John Astin is my father, Michael Tell is my biological father,” Sean told PEOPLE in 2001.

Sean has since maintained a relationship with all three men, but regards the man who raised him since birth, Astin, as his father.

“I have a good relationship with Mike. That s who I am,” he said. “I don t fault anybody, I don t fault myself or with Desi, who is like my godfather, I have such a powerful love bond with this man, he s a gorgeous human being.”

Astin said he considers his “spiritual connection” with Sean to be more important than DNA. “The greatest treasures are the treasures of the heart and Sean is a treasure. We’re very close, we have a good time together.”

He even said he’s become close with Tell over the years as well.

“His biological dad turns out to be a great guy and we’ve become friendly. He’s a good guy.”

Duke, on the other hand, wasn’t as accepting of the paternity test as the rest of her family.

“I don’t buy that test,” the actress told PEOPLE in 2001. “I can support his truth as long as my truth, if not supported, is respected. I have told him I know what I know to be true. When God looks me in the eye and says, ‘Anna Marie, you have been mistaken all these years,’ then I will consider [Tell’s paternity].”