“The Terminator” star's 25-year marriage fell apart back in 2011 after it was revealed he had fathered a son named Jospeh with their housekeeper Mildred Baena – and in a new Netflix documentary about his life the actor/politician has revealed Maria asked him about the rumours during one of their joint therapy sessions.
Speaking in new series “Arnold”, he described the moment he finally told the truth, saying: "One day, the counsellor said: “Today Maria wants to be very specific about something. She wants to know if you’re the father of Joseph. I thought my heart stopped. And then I told the truth.
“’Yes, Maria. Joseph is my son’. She was obviously crushed by that.”
Schwarzenegger and Shriver married in 1986 and welcomed four children together before they split in 2011 following the revelations about the Hollywood star's affair with Mildred.
He explained Mildred continued to work as the family's housekeeper after their illicit romance ended and Joseph grew up thinking his mum's ex-husband Rogelio was his dad.
However, Schwarzenegger says that as Joseph got older, it became increasingly obvious they were related. He added in the Netflix series: “In the beginning, I really didn’t know, but the older he got, the more it became clear to me. It was then just a matter of: ‘How do you keep this quiet?’”
He added: “I have caused enough pain for my family, because of my f***-up. Everyone had to suffer. Maria had to suffer, the kids had to suffer, Joseph, his mother, everyone. I’m going to have to live with that for the rest of my life.”
Schwarzenegger has looked after Mildred and even bought her a house where she could live with Joseph following the breakdown of her marriage, and the actor has grown close to his son after discovering the truth about his parentage.
He added of 25-year-old Joseph: “I saw Joseph developing into a fantastic human being.
“It was wrong what I did but I don’t want Joseph to think he’s not welcome in this world because he is very much welcome and I love him.
“He has turned out to be an extraordinary young man.”