The actress celebrated her partner's milestone 70th birthday on Wednesday with an Instagram post highlighting all the qualities she loves most about him, and a throwback clip of them joking about never getting married.

"Happy birthday baby! What a wild ride. No, we never got married but one thing that continues to grow is our love. You're a wild one, brilliant, lovable, childlike, perfectly maddening, a father supreme and deeply funny!" Hawn, 75, wrote. "I can't imagine my life without you at any age, Kurt Russell. You're the catch. And you're all mine."

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Hawn's daughter Kate Hudson — who was raised by Hawn and Russell alongside her brothers Boston Russell, Oliver Hudson and Wyatt Russell — also wrote a loving post to the man she sweetly calls "pa."

"I'm gonna gush cause I don't often about this man but I figure since today he turns 70 I'm gonna let it out. Plus he'll never see this," Hudson, 41, began her post, next to a throwback family shot of Hawn, Russell and their four kids.

"I often wonder how how different our life would have been if he never entered the picture. How different I would be. Let me fill you in," Hudson continued, describing all the different kinds of "dad" he is.

"His laugh will echo through generations as powerful as his concocted stories of grandeur that may or may not be true (may we never know). He's an original. One of kind. A powerful, intelligent, talented, loyal family man. He has taught me that we can all exist with immense love through our differences. And his dedication to my mother and their fight for love forever is as admirable as it gets," she wrote. "I love this man so much!"

"A note for all dads of girls. He gave me the gift of confidence instilling a knowingness in me that I deserved everything I worked for and I knew that he'd always have my back in whatever challenges may lay ahead. When you have a dad who gives you permission to be confident you live courageously. And that's my insta love letter to my dad who has lived 70 years today. ❤️ Happy Birthday Pa. How bout we give some big Hip Hip Hoorays to this wild man!" she added in the end.

Hawn and Russell's family has remained incredibly close as their kids have gained fame in their own acting careers and started families. Most recently, the majority of the clan got together for Hudson's big night at the Golden Globes Awards, where she was nominated for best actress for Music.

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In one incredible moment, as Hudson's category was being presented, the actress appeared onscreen surrounded by her famous family.

Appearing in the shot were Hudson's three kids: daughter Rani Rose, 2, and sons Bingham, 9, and Ryder, 17. They were joined by Hudson's boyfriend Danny Fukijawa, with whom she shared\s Rani, and her brothers Boston and Oliver, along with his wife and their three kids, and several other people. Hawn and Russell sat happily in the mix surrounded by their brood.