Arnold Schwarzenegger congratulates his son Joseph Baena as he graduates college

Arnold Schwarzenegger looked like the proudest dad of all as he attended the graduation of his son Joseph Baena yesterday.

The Austrian Oak was there for the ceremony at Pepperdine University in Los Angeles, as 21-year-old Joseph scored his diploma in business administration.

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Posting a snap of the pair, Arnie beamed: “Congratulations Joseph! ‘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!”

Joseph is the son he had with Mildred ‘Patty’ Baena, his former housekeeper, an affair which spelled the end of the actor’s 25-year marriage to Maria Shriver, a member of the Kennedy dynasty.

He was born just a few days after Shriver had given birth to her and Schwarzenegger’s fourth child, Christopher.

The budding business magnate also posted his own pictures on Instagram, posing with his mother, adding: “Some of the best times of my life are because of this school and the people in these pictures.

“I’m am so incredibly grateful to have the privilege to study at and graduate from such a beautiful and high caliber school.

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“I now have my degree in business administration and with that, I believe this is only the beginning of a new road. Let’s see where it takes us!”

The former Governor of California often hangs out with Joseph, the father and son bonding over lagers during Arnold’s regular jaunt to Oktoberfest in Munich.