Five year-old Prince George is one of the couple’s two pageboys – Louis de Givenchy, 6, (son of Zoe De Givenchy and Olivier De Givenchy) is the other.
Princess Charlotte, 3 is the youngest of six bridesmaids on the day, who also include Peter and Autumn Phillip’s daughters Savannah, 7, and Isla, 6; Zara Phillips eldest child, Mia, 4; and Princess Eugenie’s goddaughter Maud Windsor, 5.
The other notable inclusion is that of Robbie Williams’ six-year-old daughter, Theodora.
Pop star Williams and his wife and fellow X-Factor judge Ayda Williams have been friends of Eugenie and her sister Beatrice for years.
They are protective over their young children, and choose not to show their children’s faces when they post on social media.
Lady Louise Mountbatten-Windsor, 14, and Viscount Severn, 10, have also been given special roles on the day.
George and Charlotte have had plenty of practice in a bridal party, having stolen the limelight at their Auntie Pippa’s wedding in May 2017 and most recently at Kate’s friend Sophie Carter’s nuptials in September.
More than 800 guests will gather in Windsor, five months after the Duke and Duchess of Sussex had their nuptials at the same venue.
Prince George and Princess Charlotte were pageboy and bridesmaid at Pippa Middleton’s nuptials in 2017, then at the wedding of their uncle Harry to Meghan Markle in May, and carried out duties at the marriage of Kate’s friend Sophie Carter last month.
George, who attends private school Thomas’s Battersea, is thought to be missing school to attend the royal wedding.
But private schools are exempt from the £60 penalty which can be levied on parents who take pupils on term-time holidays from state schools without permission.
Maud Windsor – the granddaughter of Prince and Princess Michael of Kent – is a classmate of George’s.
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