Kate's brother James Middleton expecting first child with wife Alizee Thevenet

Prince William and Catherine, the Princess of Wales are going to be an uncle and aunt again.

Catherine's younger brother James Middleton has announced that he and his wife Alizee Thevenet are expecting their first child.

"We couldn't be more excited … well Mable might be ❤️," Middleton, 36, wrote on Instagram alongside a photo of his dog Mable staring at Thevenet's growing baby bump.

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On Middleton's company's Instagram page, he shared an alternate angle of Thevenet's bump, this time with to of their dogs smiling up at the camera.

"We have a new member of the pack coming soon, we couldn't be more excited 🐾 ❤️," he shared on the Ella & Co. page, which is named after his late dog Ella.

Middleton then wrote in both posts: "It was a very difficult start to the year after losing my beloved Ella however we will end the year with the most precious little addition to our growing family ❤️."

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It was in 2021 that Middleton – who is not shy about being a proud dog dad to Zulu, Inka, Luna, Mabel, Nala, and Isla – and Thevenet tied the knot.

Their new baby will be Carole Middleton and Michael Middleton's seventh grandchild, and a cousin to nine-year-old Prince George, eight-year-old Princess Charlotte, and five-year-old Prince Louis.

Catherine and James Middleton's 39-year-old sister Pippa Matthews (née Middleton) also has three children of her own – Arthur, Grace and Rose – with James Matthews.

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It's all thanks to Middleton's late dog Ella, he's previously said, that he's married to Thevenet.

"The two of us were at the South Kensington Club in Chelsea," Middleton told The Telegraph in 2019. "Ella was lying at my feet under the table; realising she might want some water, I trusted her to take herself to the water bowl across the terrace. However, she made a beeline for Alizee. Rather embarrassed, I went over to apologise and bring Ella back."

Thevenet, however, thought Middleton was a waiter, and actually ordered a drink from him while patting Ella.

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"Little did I know, I had just met my future wife, all thanks to Ella," Middleton told the publication.

"If I hadn't trusted Ella, I wouldn't have brought her to the South Kensington Club, and she wouldn't have been able to say hi to the woman who became my fiancée."

The couple got engaged in 2019, and after the pandemic delayed their wedding, tied the knot in the south of France in September 2021.