Prince William and Prince Harry arrive at the Canadian National Vimy Memorial in Vimy, France on April 9, 2017.
London CNN  — 

The late Queen Elizabeth II’s eight grandchildren will stand vigil beside her coffin in Westminster Hall on Saturday evening, a royal source told CNN.

Prince William, the Prince of Wales, will stand at the head of the coffin, and Prince Harry, the Duke of Sussex, will stand at its foot for the 15-minute vigil, according to the source. At the King’s request, both will be in uniform.

Catherine, Princess of Wales, Prince William, Prince Harry and Meghan, Duchess of Sussex on the long Walk at Windsor Castle on September 10, 2022.

The Queen’s other grandchildren will be wearing morning coats and dark formal dress with decorations, the royal source said.

The source added that the Prince of Wales will be flanked by Zara Tindall and Peter Philips, who are the children of Princess Anne. The Duke of Sussex will be flanked by Princesses Beatrice and Eugenie, the daughters of Prince Andrew, alongside Prince Edward’s children, Lady Louise Windsor and Viscount Severn.

The grandchildren, at the King’s invitation, are very eager to pay their respects – just as their parents are doing the previous evening, the source told CNN.

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