Like father, like son!

University of Southern California freshman Patrick Schwarzenegger, 19, shared a sweet photo from his childhood via Instagram October 18. The image shows his shirtless father, Arnold Schwarzenegger, 65, holding him above the pool as Patrick flexed his tiny muscles. "Getting jacked since the early days," Patrick wrote in the caption.

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Patrick is just one of the four children Arnold has with estranged wife Maria Shriver, 56. Married more than two decades, they are also parents to Katherine, 22, Christina, 21, and Christopher, 15. During their marriage, he also fathered another son, Joseph, 15, with housekeeper Mildred Baena.

Arnold spoke about the affair that "destroyed" his family earlier this month while promoting his new book, Total Recall: My Unbelievably True Life Story.

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"It was a situation where I couldn't even blame anybody else but myself, because my wife was a fantastic wife. She was a great friend, she was a great adviser, everything, great mother," he said on Hannity. "I mean, my kids were fantastic. The thing that I cherished the most, you know, I destroyed by some stupid things that I've done," Schwarzenegger said. "For me, it's important to kind of rebuild again, get the trust back with the kids, with my wife."

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"Maria has been extraordinary throughout this whole process," the former bodybuilder added. "Extraordinary also with bringing the children together and making sure that we celebrate together when there's a graduation or when there's a birthday or Valentine's Day or Easter, or Christmas -- stuff like that. She's been great. The kids have been really great. I'm thankful about that."

This article originally appeared on Cute! Young Patrick Schwarzenegger Mimics Dad Arnold in Vintage Picture