It's often said that the secret to a solid relationship is the basis of a good friendship, so it's no wonder that the Prince and Princess of Wales have just that.
Former royal butler Grant Harrold, who knows William and Kate from their dating years, has pointed out the similarities between the Waleses and William's late grandparents, the Queen and the Duke of Edinburgh.
Speaking at an etiquette dinner hosted by Press Box PR, Grant told HELLO!: "The thing about William and Kate is that they very much remind me of the late Queen and Prince Philip, because they were a team, they were a partnership, and the two of them are very much like that. So weirdly, it's almost history nicely repeating itself.
"The two of them are very much best friends and make a good team. They have a really good sense of humour. When there are jokes, they're both involved in it, and they were always fun to be around. When one of them got the giggles, the other got the giggles. So it was really sweet.
"That's why I was devastated back in the day when they split because I really wanted them to get married. So I was quite glad when they actually did and they tied the knot!"
Grant added: "I think Kate will be a very good queen. She's literally gone from a completely different background into this royal world. She's taken it on and embraced it and made a good job of it."
William and Kate celebrated their twelfth wedding anniversary this year. They are the proud parents to Prince George, ten, Princess Charlotte, eight, and five-year-old Prince Louis.
The late Queen Elizabeth II, meanwhile, and her husband Prince Philip were married for 73 years until the Duke's death in 2021. As well as William's father King Charles, they also had Princess Anne, Prince Andrew, and Prince Edward.
It's clear William is incredibly protective of his wife and three children, and prepared Kate for her royal role before their 2011 wedding. Last month, they stepped out for the Royal Variety Performance, where, according to a body language expert, William displayed protective gestures.
The outing came just two days after the release of Omid Scobie's controversial book, Endgame, where in the Dutch version, two senior royals were named as having expressed "concerns" over the possible skin colour of the Duke and Duchess of Sussex's son, Prince Archie, before he was born.
"From what I could see from their entrance, William looked determined to protect his wife as they stepped out of the car and onto the red carpet," body language expert and Sunday Times Bestseller of You Only Live Once, Noor Hibbert, told HELLO! "They never fall short of showing up looking like the picture-perfect regal couple.
"William puts his hand on her back in a gesture that is almost steering her like a protective father would do to a vulnerable child. This shows him protecting her from the crowds and her smile back shows her appreciation."
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