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Famed bodybuilder, actor and politician Arnold Schwarzenegger looked pumped up with pride Saturday as his youngest child, Joseph Baena, graduated from college.

The beaming dad posted a photo of himself congratulating his 21-year-old son, who was wearing his cap and gown from the commencement at California’s Pepperdine University.

“Congratulations Joseph!,” the action-movie star and former Republican governor of California wrote. “Four years of hard work studying business at Pepperdine and today is your big day! You have earned all of the celebration and I’m so proud of you. I love you!”

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Baena was the offspring who resulted from scandal, when Schwarzenegger had an affair with his former housekeeper, Mildred Baena, while he was still married to Maria Shriver, the NBC News correspondent and member of the Kennedy and Shriver political clans.

In reaction to Saturday’s photo, some fans praised Schwarzenegger for treating Baena just as any proud parent would.

“Props to you Mr. Schwarzenegger for stepping up and publicly acknowledging Joseph as your son,” one Twitter user wrote.

Earlier this year, Baena attracted internet attention when he posted photos in which he re-created some of his famous dad’s classic bodybuilding poses.

Since leaving the California governor’s office in 2011, the 71-year-old Schwarzenegger has had mixed success in trying to revive his acting career.

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But he has remained in the public eye in part through social media, including for messages about President Trump.

In March, Schwarzenegger blasted the president for some comments about the late Sen. John McCain, R-Ariz.

"I just think it’s a shame that the president lets himself down to that kind of level," Schwarzenegger said at the time.

For his part, Trump has criticized Schwarzenegger, in particular for the actor’s failure to match Trump's ratings when Schwarzenegger took over as star of “The Apprentice” after Trump entered politics.

"Wow, the ratings are in and Arnold Schwarzenegger got "swamped" (or destroyed) by comparison to the ratings machine, DJT," Trump tweeted in January 2017.

Schwarzenegger's four other children are daughters Katherine, 29, and Christina, 27, and sons Patrick, 25, and Christopher, 21.