Arnold Schwarzenegger has paid a touching tribute to his son Joseph Baena in honour of his 20th birthday this week. Taking to his Instagram page on Monday, the Terminator star shared a picture of the father-and-son duo exercising together at the gym. In the caption, the 70-year-old wrote: "Happy birthday Joseph! You're a fantastic son and a great training partner. You get stronger and smarter every year and I'm so proud of you. I love you."
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The sweet note comes just a few days after Arnold's other son Christopher Schwarzenegger celebrated his 20th birthday. Alongside a throwback snap, the actor wrote: "Happy birthday Christopher! You're a wonderful student, a hilarious and kind soul, and a fantastic son. I'm so proud of you, I love you, and I can't wait to see what's next." For Joseph’s birthday last year, Arnold and his son enjoyed a trip to Oktoberfest in Germany, where the pair treated themselves to a selection of beers at the famous festival.
Not much is known about Arnold's relationship with his son Joseph, whose mother is the Hollywood actor's former housekeeper Mildred Baena. Mildred worked at the Schwarzenegger household for 20 years but left her job when she found out she was expecting Arnold's baby. She gave birth to Joseph in October 1997. One month later Arnold's then-wife Maria Shriver gave birth to the couple's fourth child, Christopher. Arnold is also a proud father to daughters Katherine, 27, Christina, 26, and son Patrick, 24, from his marriage to Maria Shriver.
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In 2015 Arnold opened up about his "fantastic" son Joseph. "He's terrific and he totally understands the situation," the actor told SiriusXM host Howard Stern. "So, it all has worked out… It's a very tough situation for him. It's a very tough situation for my kids, very tough situation for my family. It was tough for everybody. But it has happened and now we have to figure it out, right?"