Kate Hudson affectionately calls Kurt Russell 'pa' and was raised by the Hollywood actor from a young age.
And on Wednesday, the Music star paid a heartfelt tribute to Kurt as he celebrated a milestone birthday.
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Taking to Instagram, the mother-of-three shared a sweet throwback photo of herself as a little girl alongside her siblings Oliver Hudson and Wyatt Russell, Kurt's son Boston and her mother Goldie Hawn.
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In the caption, Kate wrote: "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.
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"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.
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READ: Oliver Hudson pays heartfelt tribute to Goldie Hawn and Kate Hudson
"He's a pick up your boot straps kinda dad. Don't cry, shake it off you’re ok, kinda dad. Don't let 'em push you around you got this, kinda dad.
"Don't listen to the noise you're doing great, kinda dad. Shake those hips like no one's watching, kinda dad.
Kate Hudson paid a heartfelt tribute to Kurt Russell on his 70th birthday
"Always get back on the horse, kinda dad. Never miss a show, kinda dad. Kids before anything, kinda dad.
"Work hard play hard, kinda dad. My girl can rule the world, kinda dad. 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).
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"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.
Kate Hudson was raised by Kurt Russell from a young age
"And his dedication to my mother and their fight for love forever is as admirable as it gets. 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 lied ahead.
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"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.
Kurt and Goldie Hawn with their children and grandchildren
"Happy Birthday Pa. How bout we give some big Hip Hip Hoorays to this wild man!"
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Fans were quick to react to Kate's sweet words, with Kurt's former co-star Dakota Fanning being one of the first to respond, writing: "The BEST." Another follower added: "Such beautiful words," while a third remarked: "This is so beautiful."
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