Kate Middleton Is the Big Sister Prince Harry Never Had

The royal family makes it easy to wax poetic about romance — especially where it concerns Harry and Meghan, and Will and Kate. But the ties between royals that aren't on full display 24/7 are arguably more interesting.

Markle's BFF status with both Prince Charles and Queen Elizabeth is a well documented example of that, but there's yet another solid royal friendship that doesn't get nearly as much sunshine: the tight bond between Prince Harry and Kate Middleton.

The siblings-in-law are often photographed at events alongside Prince William, but their genuine one-on-one comradery is all their own. Kate and Harry are rarely photographed by themselves, but the truth is that they get along far better than people give them credit for.

The two first met after William started dating Kate more than a decade ago and have been chummy ever since. In a profile of Prince Harry for Newsweek, their bond was even compared to Harry's relationship with his mom, the late Princess Diana.

"There was no filling the hole left by Diana’s death, and Harry seemed to be growing up without someone emotionally available he could lean on. Kate has helped fill some of that gap," the piece said. "When she and William got engaged, Harry called her the big sister he never had. He often pops into their apartment at Kensington Palace, where she cooks him a meal — roast chicken is reportedly a particular favorite."

It goes beyond roast chicken and house visits; Kate also played a key role in Harry's budding relationship with his future wife, Meghan Markle. Before asking Meghan to marry him, Harry reportedly sought Kate's advice and approval first, which really tells you everything you need to know about what they think of each other behind closed doors.

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A source told Grazia earlier this year that as soon as things became serious between Meghan and Harry's relationship, the prince insisted that Kate meet her. "Harry and Kate are very close, she’s been like a mentor to him and he wanted her seal of approval," the source said. "Kate is different to Meghan in many ways, but she has made great strides to help Meghan settle in."

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Meghan is now seemingly returning the favor after picking up on how Harry and Kate interact.

"Harry has always been keen to make his sister-in-law relax and giggle more in public and it looked very much as though the confident and slightly more spontaneous Meghan might be taking on that role of her own accord," body language expert Judi James reported after Kate and Meghan watched a tennis match together earlier this year.

A tight bond, indeed. Move over, Meghan Markle and Queen Elizabeth, there's a new best friendship in Kensington Palace.