Kate Middleton's biggest fear for sister Pippa's wedding is one all mums will relate to.

Ahead of her sister Pippa’s wedding this weekend, there’s one thing worrying Kate Middleton.

And it’s a fear many parents will relate to.

While the Duke and Duchess of Cambridge watch Pippa, 33, marry James Matthews, 41, from their seats, their children will feature in the ceremony.

And according to a friend, Kate is a bit nervous about how George, three, and two-year-old Charlotte will behave.

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Andrew Bates, who has worked on audio at royal events for more than 20 years, told the Daily Mail Kate shared her concerns while chatting to him and his wife at a Buckingham Palace garden party on Tuesday.

“She said that they were all really looking forward to her sister’s wedding at the weekend but she was a bit worried about how her children might behave,” Bates, 55, said.

“She said she was hopeful that they would be good but you never know at that age.”

It’s believed George will act as a page boy at the Saturday ceremony at the Middleton’s local church of St Mark’s Church in Englefield, Berkshire, while Charlotte will be a bridesmaid or flowergirl.

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