Arnold Schwarzenegger shares Father-Son Gym photo to celebrate his love child's 20th Birthday

US actor and politician, Arnold Schwarzenegger shared this Father-Son gym session photo to celebrate Joseph Baena who turned 20 on Monday. Joseph is the son he had with his house-keeper while married to Maria Schriver.

The proud father accompanied the photo with a sweet note on Instagram.

“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,” the actor wrote in the caption.