Inside the moment George, Charlotte and Louis met their baby cousin

James Middleton has opened up about fatherhood in his new memoir, including the moment his sisters, the Princess of Wales , Pippa Matthews and their respective children, met his baby son Inigo for the first time.

The entrepreneur, 37, welcomed his first child with Alizée Thevenet in September 2023, with James also sharing his son's birth story and touching middle name in his book, Meet Ella: The Dog Who Saved My Life .

Kate and William are parents to Prince George , 11, Princess Charlotte , nine, and six-year-old Prince Louis while Pippa and her husband James Matthews share Arthur, five, Grace, three and two-year-old Rose.

Describing the moment his nieces and nephews met their baby cousin, James wrote: "On the first weekend after his birth - it is hard to believe he is only two days old - my sisters and their children come to visit and we all have lunch together at Mum and Dad's.

"There are cries from the cousins of 'Was I ever that small?' and they take it in turns to cuddle Inigo in their laps. They've worked out that there is a ten-year age gap between George and Inigo and they can't wait for him to be big enough to join in their adventures.

"Mum and Dad are delighted by their new grandson, but Mum seems mildly incredulous that her little boy now has a son of his own. She laughs because she still thinks of me as her baby."

© Getty

James and Alizée quietly celebrated their little boy's first birthday last week on 21 September ahead of the release of James's book on Thursday.

The couple, who married in 2021, have shared a handful of photographs of Inigo since his birth but have opted to maintain his privacy by not showing his face.

© Instagram

In his book, James also shared how his sisters have lent some of their children's old clothes for their nephew.

Speaking to HELLO! , James said: "They are milestones, because [my sisters] remember when their child was wearing something, and how old they were – it takes them back. It's been a lovely thing for them."

© Kensington Palace

He added: "He's fortunate to have older cousins who can now pick him up and show him things, and as he grows up, they'll be able to look out for him. There's definitely an element of curiosity [about] a baby that they have."

James praised his sisters, saying: "It's been wonderful, seeing them become mothers and being so dedicated and strong. I'm in awe of that."

"I've been fortunate to see how my sisters have done it, and take tips along the way – some I take on board, and others I'm like: 'Hmm,'" he quipped.

LISTEN: Why the Princess of Wales decided to release incredible family video

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