Credit: Brian To/FilmMagic

Baby mama drama! 

The ex-husband of Mildred "Patty" Baena, the alleged mother of Arnold Schwarzenegger's love-child, is breaking his silence about his former wife's infidelity.

In an interview with Entertainment Tonight, Rogelio Baena says he thought Schwarzenegger's child, now 13 years old, was his own biological son all along. He learned that the boy was not his only one week ago.

He went on to call the situation a "betrayal."

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Rogelio was married to Patty for ten years, and says he'd like to tell his son: "I am your father. That's all. 

"Arnold Schwarzenegger for me, [was] my hero," he tells ET. "Maria is destroyed."

Despite encouraging her children with Schwarzenegger to "forgive their father," Maria Shriver, 55, is reportedly filing for divorce from her husband of 25 years later this week.

For more of Rogelio Baena's interview, tune in to Entertainment Tonight on Tuesday and Wednesday.