Meghan Markle and Kate Middleton. (Photo/Courtesy)

Meghan Markle had an "unrealistic expectation" of her relationship with sister-in-law the Duchess of Cambridge, a royal editor has claimed. While many royal watchers assumed Meghan and Kate would become close friends, especially when they lived just a few doors apart at Kensington Palace, it ended up being quite the opposite.

A new book about the couple, Finding Freedom, claims that the two women didn't have a fallout as such but admits there was tension and "awkward moments" between them. But Emily Andrews, the Mail's royal editor, claims that Meghan expected too much from her very busy sister-in-law. Speaking on Channel 5 documentary Meghan & Harry: The New Revelations, she explains: "I think it seems that Meghan had a very unrealistic expectation of her relationship with Kate.

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"If you look at it from the Cambridges' point of view, they don't know this woman at all. From their point of view they absolutely did welcome her into the family. "William and Kate invited her invited Meghan and Harry to Apartment 1A. Kate met Meghan pretty early on in the relationship. "I think from William and Kate's point they did try and help as much as possible, but they were at a very different stage of life."

And she's not the only royal expert to have these thoughts, with Vanity Fair's Katie Nicholl adding: "While there might have been an expectation from Meghan that Kate was going to sit down and show her the ropes, perhaps that was an unrealistic expectation.

"The Duchess of Cambridge is a busy woman, but Meghan clearly took that personally."

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Finding Freedom makes multiple claims about Kate and Meghan's friendship, including saying that the Duchess of Sussex "didn't lose sleep" over their difficult relationship. Authors Omid Scobie and Carolyn Durand claim: "Meghan would agree with the assessment that the duchesses were not the best of friends. Their relationship hadn't progressed much since she was Harry's girlfriend.

"But they were not at war with each other, either. There were awkward moments, such as the day the women happened to cross paths at Kensington Palace (in early 2017, when Harry and Meghan were still only dating), and although both were heading out to go shopping - in the same street - Kate went in her own Range Rover."