If you have a sibling, you'll likely be familiar with that sense of friendly rivalry - and Prince Charles and Princess Anne are certainly no different.
It comes with the territory of course - you'll likely never have others that can understand you so well, yet annoy you so much at the exact same time.
In the latest series of The Crown, Charles and Anne's young adult years are showcased like we've never seen it before, and it's certainly led us to wonder exactly what their relationship was like in real life.
Sure, most of us are familiar with the rumoured feud that's lasted for decades between Charles, Anne and Duchess Camilla, who married the future king after his tumultuous marriage to the late Princess Diana.
But in the hit Netflix series, we see a side to the siblings' relationship that's genuinely refreshing - in fact, the pair seem to really lean on each other.
That's why we thought it pertinent to take a closer look into how the two really got along back in the day.
Born two years apart, Prince Charles and Princess Anne would undoubtedly have shared a close relationship, but it's likely there would have been a least some distance between them.
Indeed as an heir to the throne, Charles was understandably under a lot more pressure than his siblings were, and that would likely have impacted his relationships with them.
That being said, their relationship in the third season of The Crown is shown at one point to be quite close, with the pair sharing a chat over the phone to discuss their misgivings with some of the royal obligations bestowed onto them.
From this, it's possible to see a rather sweet supportive connection the siblings shared - and we can imagine this depiction wouldn't have been far from the truth in real life.
While the details are murky, it has been reported that Princess Anne once had a relationship of sorts with Andrew Parker Bowles, who later married Camilla, Duchess of Cornwall.
In fact, some reports state Camilla was actually seeing Andrew when he embarked on his romance with Anne.
It seems this might have awakened a feud between Camilla and Anna, and has bubbled ever since.
Princess Anne married Captain Mark Phillips, to whom she had two children with, Zara Tindall and Peter Phillips.
But the pair separated in 1992, and Anne remarried Timothy Laurence, to whom she has remained with to this day.
Whatever really happened in the past, nothing suggests the pair have any bad blood between them now.
Indeed Anne is still seen at engagements with Charles and Camilla, with the royal even being spotted laughing with her brother at one of his 70th birthday celebrations last year.
So with that said, the siblings' relationship might have had its ups and downs, but really, what family doesn't?
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