Kate chose a beautiful family photo showing her laying on Kurt's chest with her arm wrapped around his waist, while the actor can be seen stroking her hair.
WATCH: Kate Hudson's new family video has fans asking the same thing
She wrote: "Fun, adventurous, passionate, determined, honest, devoted, amazing father and the best head of hair in Los Angeles! Lucky us! Love you Pa! Happy Fathers Day."
Kate's mum Goldie Hawn was quick to comment on the post – and later revealed her partner's sweet reaction. "Honey this picture speaks volumes," she initially wrote, adding three red love hearts.
Kate moved Kurt to tears with her loving message
She later shared: "Honey I showed this to daddy. Here's his message…
"Birdie, mommy just showed me this picture, this perfect Father's Day present. I've never seen it before. Wow…it’' a killer. Lotta water under the bridge…it's kinda hard to see it though cause all that water seems to somehow have found its way into my eyes…thanks for making me the luckiest father in the world sweetheart. I love you, Pa."
Kurt raised both Kate and her older brother Oliver
Goldie welcomed Kate and her older brother with her ex-husband Bill Hudson; he filed for divorce in August 1980, one year after Kate's arrival.
The siblings have been raised by Goldie's long-term partner Kurt and affectionately refer to him as 'pa'.
Goldie was married to Bill Hudson from 1976 until 1982
Goldie and Kurt have been together since Valentine's Day 1983 and celebrated 39 years earlier this year. Together they share son Wyatt Russell.
The celebrity couple are also doting grandparents to seven grandchildren, who keep them on their toes. Goldie previously told Australian Women's Weekly: "A good family is the answer to happiness.
Family is everything to Goldie and Kurt
"I look at our kids and grandchildren and there's nothing in the world that could make me as proud as I am of all of them."
Goldie and Kurt primarily live in LA, close to daughter Kate, but also have a beautiful home in Colorado up in the mountains, where they enjoy spending quality time with the entire family.
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