Princess Kate's brother, James Middleton, has revealed the cheeky reactions from his nephew and niece, Prince George and Princess Charlotte, when he introduced them to his now-wife for the first time.

In his new book Meet Ella: The Dog Who Saved My Life, Middleton has given an in-depth account of his life story to date, covering his emotional battle with clinical depression as well as the major family milestones that came when his older sister, Kate, married the heir to the British throne.

In an extract of the book, published by the Mail on Sunday in Britain, Middleton recounted the events of 2018, the year met his now-wife—French finance professional Alizee Thevenet. In it he has revealed how he introduced her to his family, including Prince William, Kate and their three children, by accident.

Soon into their relationship, Middleton revealed that he and Thevenet decided to spend the night at his parents' house in Berkshire, southeast England, after attending a wedding nearby.

James Middleton, left, photographed in London in July 2022; and, right, Prince George with Princess Charlotte photographed in Wales in June 2022. In his new memoir, Middleton has shared touching insight into his relationship with... James Middleton, left, photographed in London in July 2022; and, right, Prince George with Princess Charlotte photographed in Wales in June 2022. In his new memoir, Middleton has shared touching insight into his relationship with his nephew and niece. Dave Benett/Getty Images for Bulgari/Samir Hussein/WireImage

Letting themselves in while everyone was in bed, the couple went to his room where they fell asleep—and where Middleton was unexpectedly woken up the next morning by his "giggling" niece and nephew.

"I'm woken at 7.30 a.m. by giggling at the bedroom door. It's George and Charlotte, my nephew and niece," he wrote. "I hadn't ­realised all three children are staying for the weekend with my sister and William.

"Alizee is still sound asleep, so I gently shush the children and we go downstairs where Catherine and William are drinking their early morning tea in the kitchen. I'm about to take a cup up to Alizee when she appears at the kitchen door. She has just got out of bed, her hair still tousled, and she is wearing one of my shirts."

Middleton told readers that his then-girlfriend confidently introduced herself to the prince and princess, whereupon they appeared to form a warm connection. He added that as they spoke, George and Charlotte began asking him "cheeky" questions.

"We're soon all chatting and the children are asking all kinds of cheeky questions at a hundred miles per hour," he wrote.

"How come we weren't there when they went to bed? And who is this lady? Is she your girlfriend? (Cue giggles from both of them.) So I tell Charlotte and George, yes, she is my girlfriend and introduce her to them, then we are all talking and laughing as if she has been part of the family for years."

Middleton and Thevenet married in France in 2021 and welcomed their first child, Inigo, in 2023. His memoir is a significant development for the Middleton family who, until now, have not spoken openly or in-depth about their family life or that of Princess Kate. The royal is close to her brother and sister, Pippa Matthews.

Alizee Thevenet and James Middleton photographed at Westminster Abbey in London, in July 2022. The couple married in 2021 and have one child. Alizee Thevenet and James Middleton photographed at Westminster Abbey in London, in July 2022. The couple married in 2021 and have one child. Dave Benett/Getty Images for Bulgari

In his book, Middleton recounts how during his mental health journey to being diagnosed with clinical depression, his sisters accompanied him to a special therapy session, both offering him their support.

"Meet Ella: The Dog Who Saved My Life" by James Middleton is published in the United States by Pegasus Books and released on September 26.

James Crawford-Smith is Newsweek's royal reporter, based in London. You can find him on X (formerly Twitter) at @jrcrawfordsmith and read his stories on Newsweek's The Royals Facebook page.

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