Goldie Hawn's two eldest children Kate and Oliver Hudson haven't always had an easy relationship with their biological father, Bill Hudson.
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The famous siblings refer to Goldie's long-time partner Kurt Russell as their 'Pa', and on Father's Day, Kate paid a heartwarming tribute to him on Instagram.
Oliver followed suit, but also made reference to Bill, admitting that the older he is getting, the more alike he realises they are.
VIDEO: Kate Hudson left in hysterics by brother Oliver Hudson's appearance
The father-of-three shared a poignant message on his social media page, which also featured a tongue-in-cheek reference to his "potential" father, Warren Beatty.
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The actor wrote: "It doesn’t really matter which one of these men is my father. "My Pa stepped in when I was 6 and made the man I am today..
"My Dad is half of me and as I get to know him I realize how alike we actually are.. and there’s a very good chance Warren Beatty is my actually father.. HAPPY FATHERS DAY!! #itsokaytocry."
Oliver Hudson paid tribute to his biological dad Bill Hudson
Fans were quick to react to Oliver's post, with one writing: "Kurt did an awesome job, Happy Father's Day to you and him," while another wrote: "You are right it doesn’t matter who your biological father is.
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"It’s about who has been there for you! You do look sooooo much like your actual birth dad, who I’m assuming is the second slide!! Like exactly like him!!"
A third added: "Wow, I didn't realise how much you look like your dad!"
Goldie Hawn with ex-husband Bill Hudson - father of Oliver and Kate Hudson
Other fans made sympathetic remarks about Goldie, as Oliver had revealed last month that she wasn't happy with him after he had forgotten to post a tribute to her on Mother's Day.
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The father-of-three posted a clip of himself on Instagram shortly after the incident, which showed him singing a witty song he had composed.
During the catchy lyrics, Oliver admitted that the women in his life were "mad" at him.
"I forgot to post on Mother's Day, everyone is mad at me. My mother, my sister, my wife and my brother, everyone hates me," he jokily began.
The Hollywood actor with his wife and children
Oliver continued: "I forgot to post on Mother's Day, and now I'm catching so much heat. My mom doesn't love me, my sister doesn't love me, no-one loves me anymore.
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"Forgot to post on Mother's Day, my mother doesn't love me anymore, but I still love all the moms in my life, a post doesn't say [expletive] I love you, I love you, I love you."
Oliver himself is a parent – a doting father to children Wilder, Bohdi and Rio, who he shares with wife Erinn Bartlett.
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