In his new documentary, Arnold, Arnold Schwarzenegger recalls the harrowing moment he came clean to then-wife Maria Shriver about his affair that resulted in a lovechild.

The former California governor says he told Shriver the truth during a marriage counseling session in 2011.

"She wants to know if you’re the father of Joseph," the counselor told the couple, referencing their housekeeper at the time Mildred Baena’s son, Joseph Baena.

"I thought my heart stopped. And then I told the truth," the actor explains in the Netflix special.

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"Yes, Maria. Joseph is my son," he told the journalist, noting she "was obviously crushed" by the revelation.

The Terminator star details that after his and Mildred's affair, he initially didn't believe he was Joseph's father, as Mildred was married at the time.

"In the beginning I really didn’t know. But the older he got, the more it became clear to me," Schwarzenegger recalls of learning Joseph was his biological son.

"It was then just a matter of, 'How do you keep this quiet?'" he admits.

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Schwarzenegger and Shriver tied the knot in April 1986. Twenty-five years later, in May 2011 they announced their separation amid reports of the Kindergarten Cop star's infidelity.

The couple share four children: Katherine, 33, Christina, 31, Patrick, 29, and Christopher, 25.

Although Schwarzenegger previously noted that his divorce was "very, very difficult" in the beginning, he doesn't miss being married.

He also said he is proud of how he and Shriver have handled co-parenting.

"She and I are really good friends and very close, and we are very proud of the way we raised our kids. If there's Oscars for how to handle divorce, Maria and I should get it for having the least amount of impact on the kids. The sweetness and kindness you see in them, that's from my wife. The discipline and work ethic is from me," the actor said.

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