From the Queen's 73-year marriage to the late Prince Philip to the Duke and Duchess of Cambridge's University love story, several members of the royal family have spoken out about their relationships.
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So what are their top tips for making their marriages work? Take a look at the heartfelt and relatable things they've said over the years...
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Zara and Mike Tindall
Former rugby star Mike Tindall revealed that it helps that he has a lot in common with his wife and Olympian Zara. In an interview with The Times, he said: "She's always been my best friend. That doesn't change."
When asked by the newspaper what the secret to a happy marriage is, Mike responded: "I don't know if I've got any top tips. She's always right, is that a top tip? I think there's a lot of balance.
"It's always been good for us being two professional sportspeople. It's a bit clichéd but you understand each other, what your motivations are. I think that's why we gel."
Prince William and Kate Middleton
Having fun is a crucial part of the Duke and Duchess of Cambridge's relationship, they revealed when announcing their engagement in 2010.
Prince William said: "Obviously we both have a very fun time together, both have a very good sense of humour about things, we're down to earth, we take the mickey out of each other a lot, and she's got plenty of habits that make me laugh that I tease her about."
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Kate added that being supportive is also instrumental in helping their relationship blossom: "You know, over the years William has looked after me, he's treated me very well – as the loving boyfriend he is, he is very supportive of me through the good times and also through the bad times."
During a BBC documentary, the couple revealed they are inspired by the example set by William's grandparents.
"I'd love to know their secret," William confessed. "I think it’s fantastic and I've regularly asked them both how they've managed it, because they are the most lovely couple. I hope Catherine and I have the same sort of future ahead of us, where we can be as happily married as they are after 68 years."
The Queen and Prince Philip
Prince Philip had been devoted to his wife ever since their 1947 wedding, and the monarch made several comments about their marriage over the years, praising her husband's support.
On their silver wedding anniversary, the Queen said in a speech: "If I am asked what I think about family life after 25 years of marriage, I can answer with equal simplicity and conviction, I am for it." Twenty-five years later she would describe her husband as "quite simply my strength and stay".
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Queen Margrethe of Denmark and Prince Henrik
Perhaps the most candid account of marriage has come from Queen Margrethe of Denmark, who revealed that it is unrealistic to expect every day to be happy.
"What is wrong today is that we expect a marriage or a relationship to be happy and successful all the time," she explained in an interview with The Sunday Telegraph.
"We forget that people who have lived together for 50 years cannot have been happy every single day. Marriage is like the weather: it changes… But this is no tragedy. It does not mean that your marriage is not working. It works again afterwards. People find one another again without great difficulty."
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Prince Harry and Meghan Markle
Prince Harry and his wife Meghan Markle have often discussed their unwavering support for one another since they began dating in 2016.
Before their royal wedding in 2018, when there was a lot of media attention surrounding their relationship, Kensington Palace released a statement saying: "Prince Harry is worried about Ms. Markle's safety and is deeply disappointed that he has not been able to protect her."
During their interview with Oprah Winfrey in early 2021, he said he was grateful to have had Meghan's support during his exit from royal life.
He told Oprah: "I'm just really relieved and happy to be sitting here, talking to you, with my wife by my side, because I can't begin to imagine what it must have been like for her, going through this process by herself, all those years ago.
"Because it has been unbelievably tough for the two of us, but at least we had each other."
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