When it comes to wholesome celebrity sibling relationships, Kate Hudson and her brother Oliver take the cake. These two actors have had incredible careers on their own, but it was their mutual support that got them through tough times in the past, built their characters, and gave them the confidence to become the amazing people they are today.RELATED: 10 Facts About Bella & Gigi Hadid's Childhood Together As SistersThey have always been very open about their friendship and how much they appreciate and love each other, but here are some interesting details readers might not know about.

7 Kate And Oliver Got Off To A Rocky Start

Though, to be fair, Oliver Hudson was three at the time. Like most older siblings, when Kate Hudson was born, Oliver didn't immediately love her. He had the normal flare of jealousy that most children have, and he made it known.

"I think my mom said it started when I came home from the hospital and he was catapulting clementines into my crib, and she had to remove him from my nursery," Kate laughed. "And it just expanded from there."

Of course, the clementine attacks diminished significantly as time went by, and it didn't take long for the siblings to become good friends.

6 Their Complicated Upbringing Brought Them Closer

Although the two of them have what could be described as 'easy lives' now, it wasn't always that way. Growing up, their childhood was difficult, with a family full of conflict, marked especially by their absent father. But Kate and Oliver found a way to turn that into a good thing, as they learned to rely on each other and build the beautiful relationship they have now.

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"I mean, the reality is that we have a very interesting dynamic, and Oliver and I had an interesting upbringing, and no matter how much conflict there was, we were always so close, and then it really kind of hit us when he went to college," Kate explained.

5 Kate And Oliver Hudson Have A Messy Relationship With Their Biological Father

The main reason the Hudson siblings' childhood wasn't a bed of roses was their father. Their mother, actress Goldie Hawn, was married to musician Bill Hudson for six years, but when they got divorced, Bill became a very absent father, inevitably impacting Kate and Oliver's lives. They barely interacted for a long time, and when they did, it was usually not very pleasant. They have even made their family issues public on several occasions, the most explicit time being when, one Father's Day, Oliver posted a picture of Kate and him with Bill, with the caption "Happy abandonment day..." and tagged his sister. Apparently, they have somewhat improved their relationship through the years, but they still have a long way to go.

4 Kate And Oliver Hudson Have A Lot Of Love For Their Stepfather

Although their father's abandonment has undoubtedly left a hole in Kate and Oliver's lives, the siblings had the good fortune of meeting another father figure who they consider their true father – their mother's partner, Kurt Russell.

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Kate and Oliver love him and are grateful that he stepped up as a parent when they needed him the most. Kurt and Goldie are still together, and they support their children every step of the way.

3 Kate And Oliver Hudson Have A Complicated Relationship With Their Half-Siblings

"You know what I’ve been thinking about lately? Dad," Kate said to Oliver last year while they were discussing their New Year's resolutions. "We’ve got four siblings we don’t spend any time with."

The siblings she refers to are Bill Hudson's three other children and Kurt Russell's firstborn son, Boston. While they have a good relationship with the Russell family, they are not as close with their step-brother Boston as they are with each other and their half-brother Wyatt Russell. The Hudson siblings are a different story, though, because the situation is more complicated, but Kate and Oliver have recently realized that it wasn't their half-siblings' fault that their father kept them apart.

"We’re sitting here like, 'We have the best family, we’re so great,' and we don’t ever acknowledge the fact that we have four other siblings. Four,” Kate continued. "So I’ve been thinking about the Hudsons, and thinking it’s important that we reach out with all of our siblings and maybe connect with them a little bit."

2 Kate And Oliver Hudson Raise Their Kids Like Siblings

Being as close as they are, Kate and Oliver want their kids to be close too. So they decided to raise their children like siblings. They live pretty close to each other, so it's not that difficult, and they have developed a lovely routine that allows them to spend time together.

"Our kids are like siblings—they want to be with each other at all times," Kate shared. "I either have the kids or I send my kids to Ollie's. Then we come over and we meet up and we have dinner."

This arrangement works perfectly, not only because it gives them plenty of family time, but because it also allows each of them to have time for themselves while their kids are with the other.

1 Kate And Oliver Hudson Have A Podcast

Knowing that, while not all siblings are as close as them, the relationship between brothers and sisters is unique and important, Kate and Oliver decided to launch a podcast where they explore the sibling dynamic. The podcast is called "Sibling Revelry", and each episode delves into the story of a set of siblings and their relationship.

"It started with Oliver and I wanting to do something together," Kate explained. "We call it 'revelry' because it's really about how we celebrate that relationship. I don't think people really talk about the importance of it." Oliver added that "It's a very dynamic relationship, one that is under-explored, I think."

The podcast is a huge success, and their great rapport is a testament to their love and friendship.

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