It was tea time on the day of the royal wedding and the Duke and Duchess of Cambridge had just wowed the crowds outside Buckingham Palace by emerging from the gates in a dark blue Aston Martin DB6 MkII featuring the numberplate "JU5T WED".

Waving from the stylish convertible, belonging to the Prince of Wales, as an RAF helicopter flew overhead, it brought a formal day of royal pomp and pageantry to a light-hearted end as the joyful newlyweds motored up the Mall to Clarence House, Prince William’s former London home.

Unbeknown to the wellwishers outside, there was another spontaneous moment of informality as the bride and groom rejected the offer of a glass of the finest champagne in favour of a pot of tea for two.

The touching incident appeared to characterise the normalcy of a couple who, only hours earlier, had been married before a global audience of millions in scenes reminiscent of Prince Charles’s wedding to Lady Diana Spencer in 1981.

Yet, a decade on, that is where comparisons end, with William and Kate thriving where his parents once faltered.

Three children later and now arguably the most pivotal post-Megxit players in the House of Windsor, the future Prince and Princess of Wales have never been under more pressure to step up in support of Queen and country.

As they celebrated their 10th wedding anniversary recently, they have just cause to reflect on what has been one of the most difficult time of their alliance in the wake of the Duke and Duchess of Sussex’s departure to the US in March last year.

As well as being the most directly affected by Harry and Meghan’s desire to move away, they have also had to suffer the ignominy of the LA-based couple’s televised outpourings to Oprah Winfrey, when Meghan accused Kate of making her cry during a bridesmaid’s dress fitting and Harry described his brother as being "trapped" in the monarchy.

However, as they celebrated their milestone anniversary, the Cambridges deserve to take comfort from the fact that they have found equilibrium in their own relationship.

For what started out as an uneven match between a blue-blooded prince and his Bucklebury-born "plus one", has now blossomed into a marriage of equals.

Sources close to the couple have long been at pains to point out that theirs is a two-peas-in-a-pod kind of partnership. As one royal insider put it: "They are both very similar in the respect that they are intrinsically quite shy people who have sometimes struggled with life in the limelight.

"When he is having a difficult time, she is the one who helps him through it, but it works both ways. He is there for her and she is there for him." Citing the "slightly competitive edge" to their relationship, the source added: "But ultimately they are very much on the same side, on the same team. There is quite a lot of affectionate joshing between them, but they have always had each other’s backs."

The Cambridges with David Attenborough... trying to lead a near normal life is of utmost importance to the family

Some may even go so far as to suggest theirs is a "seesaw" marriage, where the roles of breadwinner and child-care provider are fluid and interchangeable. Determined for one of them to always be at home to see Prince George, seven, Princess Charlotte, five, and three-year-old Prince Louis off to school in the morning and tuck them in at night, there is a sense that the couple take it in turns to have their moment in the sun, as well as putting on a united front when required.

As evidenced by the mutual giggling over their golf skills during a visit to Durham recently, they are arguably better together, notwithstanding the fact that William has made considerable headway as a statesman with solo visits to China, Jordan, Israel and Palestine, while Kate has also carved out a niche as an expert on early years learning.

According to Katie Nicholl, author of The Making Of A Royal Romance, about William and Kate’s love affair: "When they are planning their diaries, like when William went to Israel, it literally came down to looking at timing of flights to ensure that he could still be there to see the children before he left.

"When they do go away together, they have got Kate’s parents, Michael and Carole Middleton, to fall back on as well as their long-standing nanny, Maria. They have a really strong support network that they absolutely trust."

Agreeing theirs is very much a "seesaw" marriage, Nicholl says: "I think there has been a bit of a role change in this relationship in the last year. Kate’s very much been the pillar of strength, guide and mentor for William that he has always been for her.

"He’s had a really hard time with his brother, he’s really struggled with it and she’s been a rock. When he was ill with Covid – she was the one nursing him and pulling it together and putting on a united font. She’s really shown the mettle – and he loves that about her – and as such he’s let her take the lead." A palace insider agrees, but adds: "The opposite is also completely true. A lot of her growing confidence is down to him. She has never tried to be the front man and always seen herself more in a supporting role, but he’s tried to push her out of that at points because he knows what she can achieve."

Citing the keynote speech Kate made in November to reveal the key findings from a 57-page Royal Foundation report on early childhood, Nicholl adds: "That speech showed how full circle Kate has come. William has faith in her but so has the family. When he needs to be in the background, she rises to the occasion, and vice versa."

In the first three years of their marriage, when they were based on Anglesey, where William was working as an RAF search and rescue pilot, the newlyweds were criticised for shying away from full-time royal duties.

Nicholl recalls: "I remember covering their first mini tour of the UK immediately after they married and Kate was really nervous. She was still learning the ropes. If you compare that to her confident composure at the Duke of Edinburgh’s funeral then you realise what a class act she has become.

"Watching them over the past decade, they are the couple who finish each other’s sentences. As with any marriage, there have been ups and downs but they have got through them. This is a marriage based on friendship. That long courtship has stood them in good stead."

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