Duchess Kate admits she is 'a bit worried' about how her children will behave at Pippa's wedding

With just a few days until her younger sister’s wedding, Kate Middleton expressed her excitement for Pippa Middleton and James Matthew’s highly-anticipated nuptials. While at the first Buckingham Palace garden party of the season on Tuesday, the Duchess of Cambridge chatted with partygoer Andrew Bates and his wife Janet about her sibling’s big day admitting that she was looking forward to the wedding, but is slightly nervous about how her young children, Prince George and Princess Charlotte, are going to behave. Andrew revealed, "[Kate] 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. She said she was hopeful that they would be good but you never know at that age." 

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Prince George and Princess Charlotte have been given key roles at Pippa Middleton's wedding

It was previously revealed that Prince George and Princess Charlotte will serve as a pageboy and bridesmaid in their aunt’s upcoming wedding. Pippa and her fiancé are set to tie the knot on May 20 at Mark’s Church in Englefield, Berkshire in followed by a reception at the Middleton family home in Buckleberry, seven miles away from the church. While Saturday will be a family affair for the Duchess, Tuesday was business as usual for the British royal. Kate looked sophisticated at the party stepping out wearing her ice blue Christopher Kane coatdress, which she previously wore to the Opening Ceremony of the 2012 London Olympics and again in 2014 for the Order of the Garter. The mum-of-two opted for an elegant updo, which she topped off with a pale blue Lock & Co 'Sweet Delight' hat.

Along with Kate and the 8,000 guests at Buckingham Palace, a number of royal family members stepped out for the occasion including Her Majesty, the Queen, Prince Philip, Prince William, Princess Anne, Prince Edward, Princess Beatrice in addition to Prince and Princess Michael of Kent. Guests at the royal-studded event were treated to around 20,000 slices of cake, 20,000 sandwiches and over 27,000 cups of tea. Tuesday’s garden party marked the Queen’s first of four this summer. 30,000 People are expected to attend the parties this season.