Duchess of Cambridge nervous about how George and Charlotte will behave at Pippa Middleton's wedding

The Duchess of Cambridge was just one of the royals at the Queen’s first garden party of 2017.

On Tuesday afternoon, Kate and William joined the Queen and Prince Philip to welcome 8000 guests into the grounds of Buckingham Palace.

Speaking to one of the guests, Kate revealed that she was slightly nervous about how her two young children will behave at her sister Pippa Middleton’s wedding this Saturday.

“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,” he told the Daily Mail.

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

Three-year-old Prince George is set to be a page boy at the high-profile wedding with two-year-old Princess Charlotte taking on the role of flower girl.

The Duchess recycled yet another look for the springtime occasion. She chose an icy blue coat dress by Christopher Kane that had previously been seen on her twice before.

Kate first wore the pastel look to the 2012 Olympics Opening Ceremony, re-wearing it again in 2014. Yesterday, she chose a matching hat by royal favourite Lock & Co and finished off with £470 nude suede heels by Gianvito Rossi.

Preparations for Pippa Middleton’s wedding are well underway with a £100,000 glass palace being erected for the big day.

The Duchess will not be a bridesmaid due to fears of Kate outshining her younger sister. Instead, she is expected to read at the small church ceremony.

Click below to see every outfit the Duchess of Cambridge has worn while carrying out her royal duties:

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