By Prince Harry and Meghan’s own admission, the former Suits star’s relationship with her future sister-in-law got off to a rocky start well before the very public falling out that would follow.

Both the Duke and Duchess of Sussex pointed to “barefoot” Meghan’s “casual” and informally warm approach during her first meeting with Prince William and Kate as an early indicator of the trouble that would later unfold.

However, a key anecdote in the Princess of Wales’ brother’s new memoir has cast heavy doubt on that claim.

James Middleton writes about his wife Alizée’s accidental meeting with William, Kate and their children. Photo / Getty Images

In Meet Ella: The Dog Who Saved My Life, James Middleton claimed the first meeting between his future wife, Alizée Thevenet, and Kate and William had happened by accident – and that Alizée had been dressed only in his shirt at the time.

He explained that they’d decided to crash at his parents’ home in Berkshire after attending a wedding nearby, and had woken up to discover that William, Kate, and their three kids were visiting for the weekend.

“I’m about to take a cup up to Alizée when she appears at the kitchen door,” he wrote.

“She has just got out of bed, her hair still tousled, and she is wearing one of my shirts. In situations like this, Alizée is ­wonderfully French. She does not panic or rush upstairs to get dressed.

“Instead, she just greets everyone warmly as if it’s not remotely unusual to be meeting her boyfriend’s sister and brother-in-law for the first time wearing only an oversized man’s shirt.

“’Hello,’ she says, proffering her hand and with no awkwardness at all we’re soon all chatting and the children are asking all kinds of cheeky questions at 100 miles per hour.

“Then we are all talking and laughing as if she has been part of the family for years.”

Far from the informality providing awkwardness, James added that his sister was instantly taken with his girlfriend.

He wrote that Kate quietly gave him a “special squeeze”, before whispering in his ear: “She’s just great.”

Meghan Markle described her first meeting with William and Kate as ‘formal’. Photo / Getty Images

It’s a far cry from Meghan’s recollections of her first meeting with William and Kate back in 2017, which she suggested was “formal” in her Netflix series, Harry & Meghan.

“Even when Will and Kate came over and I was meeting her for the first time I remember I was in ripped jeans, I was barefoot,” she said.

“Like I was a hugger, I have always been a hugger. I didn’t realise that is really jarring for a lot of Brits.

“I started to understand that the formality on the outside carried through on the inside, that there is a forward facing way of being and then you close the door and think ‘Okay we can relax now’.

Prince Harry recalled in his own memoir Spare that there was an awkwardness in Meghan’s first encounter with his brother and sister-in-law. Photo / Netflix

“But that formality carries over on both sides and that was surprising to me.”

Harry also spoke about the stiff encounter in his memoir, Spare, describing the stark difference between the pair.

He wrote that everything had appeared to be going well, bar one detail: their outfits. ”The only possibly discordant note I could think of was the marked difference in how the two women dressed, which both of them seemed to notice,” he recalled.

“Meg: ripped jeans, barefoot. Kate: done up to the nines. ‘No big deal’, I thought.”

However, it would prove to be the beginning of a tumultuous relationship between the royal women.

Meghan later claimed that Kate had left her in tears over an issue with bridesmaid dresses in the lead-up to her wedding, that she’d taken offence to Meghan suggesting she had “baby brain” while pregnant with Prince Louis, and that she’d “grimaced” when Meghan had asked to borrow lip gloss.

Harry also detailed a tense confrontation between both couples, during which he claimed William pointed at his wife and called her “rude”, prompting Meghan to ask him to “kindly take your finger out of my face”.