Arnold Schwarzenegger is 74!
"HAPPY BIRTHDAY DADDY!" Katherine wrote alongside a series of images of herself and her dad when she was growing up. "I love you so much and can't wait to celebrate you ! Have the best day ever!! 🥰♥️🙏"
The sweet snaps included one of Katherine and her dad riding horses, as well as a silly shot of the pair playing in the pool together.
Joseph also showed his dad some love, posting a photo of himself and Schwarzenegger dining out at a restaurant. Both men smiled as they clinked their glasses together.
"Happy Birthday Dad!" Joseph captioned the post. "I hope your pump was juicy and may your day be filled with lots of schnitzel, schnapps and stogies!!!"
katherine schwarzenegger/instagram; Joseph Baena/instagram
Joseph is his youngest son, whom he fathered with his former family housekeeper, Mildred Baena. The 23-year-old has followed in Schwarzenegger's footsteps, pursuing both acting and bodybuilding. He is also a realtor.
In May, Joseph shared a selfie of himself and his dad hitting the gym for a difficult workout session.
Joseph Baena/instagram Arnold Schwarzenegger and Joseph Baena
"This selfie was taken moments before my dad suggested I do 'forced reps' for the rest of the workout," Baena wrote in the caption. "You have to go all out and absolutely NO cheating when you train with him, so you know I'm going to be hurting tomorrow."
Baena added, "Overloading on the rows, bench press, pull downs, etc... thankfully my studly training partner helped me get every last rep. This is another great approach to training and a fantastic way to build size and strength! Try it out with your training partner 💪."
Schwarzenegger commented on the post with the emoji: "💪."
Last year, Schwarzenegger became a grandpa when Katherine welcomed her first child, a daughter named Lyla, with husband Chris Pratt.
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In April, the Terminator actor said while appearing virtually on Jimmy Kimmel Live! that the new gig as a grandfather is "fantastic," but "it makes me feel old to think about now I have a grandchild."
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"But it's really great having a grandchild," he continued. "It's a beautiful, beautiful baby, baby Lyla, and I'm very proud of Katherine and Chris."
Added the former California governor: "They're doing really great together as parents."