Inside Meghan Markle and Kate Middleton’s ‘tense’ relationship

They were dubbed the new Fab Four – two dashing royal princes and their dazzling wives. But now the cozy quartet of Prince Harry and Meghan Markle and Prince William and Kate Middleton appears to be falling apart at the seams.

A growing friction between the two princes has been matched by an equally frosty relationship between their wives. And it is Markle who has found herself named as the instigator of what royal insiders claim is an “extraordinarily tense” time.

At first glance, the decision of Prince Harry and his wife to move to a new home on the Queen’s Windsor Park estate seemed natural for a newlywed couple awaiting the birth of their first child.

But by shunning moving into a Kensington Palace apartment next door to Prince William, the Duke and Duchess of Sussex have revealed serious cracks in the group dynamic.

It was suggested that Harry was annoyed that his brother had not “rolled out the red carpet” for Meghan and made her feel more welcome in The Firm. Only when their father, Prince Charles, stepped in was the spat resolved. Well, that spat, anyway.

“They have had quite a few arguments,” one royal source claims. “This is about Harry pulling away from his brother.”

As a result, Harry and Meghan will take up residence 25 miles away in Frogmore Cottage. Royal observers had expected them to move into Apartment 1 Kensington Palace — where renovations on the roof had taken place.

After years of enjoying a particularly close relationship with his younger brother, the move to Windsor comes as a huge snub to the future king and his family. Yet while there are difficulties between the two princes, many see the real reason for the group fall-out as the clash of Kate and Meghan’s very different personalities.

The American actress and the reserved middle-class girl from the Home Counties are poles apart, with very little in common. It is this lack of familiarity that is slowly breeding contempt.

As one source reveals: “They try their best to get along but they are two people from wildly different places, so it is perhaps inevitable that they will rub each other up the wrong way.”

Kate toes the royal line, almost to a fault. She dresses demurely and hardly utters a word, apparently desperate never to put a foot wrong. Many people admire her for it. But critics have labeled her boring and say she performs the minimum of royal duties, never straying too far from home.

Then along came Meghan: forceful, opinionated and go-getting — as one would expect from a woman making her way in the tough world of LA showbiz. Even before her position in the family was formalized, she was already undertaking public engagements, thirsty to meet the public and show just what an asset she could be to the House of Windsor.

Nothing would be too much trouble for her — no distance too far, no heel too high. But Meghan could not walk into the royal fold and accept its rules without a murmur. It was clear from the start she wanted to do things her way, and Harry was happy to let his wife do the talking.

This summer, as the headlines hovered over Harry and Meghan — their barnstorming tour of Australia and New Zealand, for instance — William and Kate looked dull by comparison. But now? Yesterday the Sun told of an uncomfortable scene between the two sisters-in-law before Meghan’s wedding, at a bridesmaid dress fitting for Princess Charlotte.

Royal sources said the “stressful” fitting became too much for Kate, who was left shaken and in tears. That followed revelations of a row after Meghan had been invited to choose a tiara from the royal collection for her wedding day.

Meghan, who has an eye for attention-grabbing moments — this week being shown in previously unseen photos trying on striking headdresses while exploring her family ancestry in Malta in 2015 — selected one featuring emeralds. But she was then told she would have to choose another.

Prince Harry backed her original choice, even raising his voice to staff, saying: “What Meghan wants, Meghan gets.” Eventually, the Queen had to step in and bring her grandson into line.

While these difficulties could simply be seen as the Bridezilla moments of an anxious woman ahead of the biggest day of her life, some of those who have been around her say Meghan can be difficult and demanding. She is said to “snap” and to think nothing of bombarding staff with emails and calls as early as 5 a.m.

Staff reportedly gossip about her and Harry, with some speculating the union could be over within five years. Meghan’s former personal assistant Melissa Touabti — who previously worked for pop star Robbie Williams — quit just six months after the wedding and has refused to say why.

Harry’s long-standing private secretary Ed Lane Fox also left his job earlier this year. And deputy communications secretary Katrina McKeever quietly departed in September. But the move to Frogmore could give the Fab Four the space they so desperately need.

Where the respective couples choose to hang their festive stockings could signal how serious this rift really is.