Duchess Sophie just wore her most famous Ascot hat and Princess Kate's handbag

On Monday afternoon, the royals attended the annual Garter Day service at Windsor Castle. Dressed in their best finery, members of the firm joined King Charles and Queen Camilla for the traditional celebration commemorating the ancient Order of the Garter.

Sophie, Duchess of Edinburgh was spotted arriving, looking as stunning as always, rocking a cream dress which was printed with eye-catching pink florals.

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 The mother-of-two added white high heels, and also carried a white Strathberry handbag - a very similar style to the one the Princess of Wales has been snapped sporting on a variety of occasions.

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We also spied that Prince Edward's wife was wearing a delightful, complementary hat.

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The stunning piece was also cream, with a pink trim and the royal actually wore it to Ascot last year. It is widely regarded as one of her most loved pieces of headgear due to the pale pink, wide-brimmed shape and the bold bow-like creation on the top. So dazzling!

What is Garter Day?

Garter Day sees Ladies and Knights of the Order of the Garter – the country’s oldest and most senior Order of Chivalry – process down the hill from the Berkshire castle’s State Apartments to St George’s Chapel, dressed in white plumed hats and dark blue velvet robes, watched by crowds of onlookers.

The installation of new Companions of the Order – including composer Andrew Lloyd-Webber who has been made a Knight Companion – will take place during the service.

Theatre impresario Lord Lloyd Webber, whose hit musicals include The Phantom Of The Opera, Cats, Jesus Christ Superstar and Joseph And The Amazing Technicolor Dreamcoat, will also attend a private investiture in the castle’s Garter Throne Room earlier in the day.

Also being invested will be the Duchess of Gloucester as a Royal Lady of the Garter, as well as Lord Kakkar, emeritus professor of surgery at University College London and Air Chief Marshal the Lord Peach, who have both been made Knight Companions.

Founded in 1348 by Edward III, the Garter is awarded by the sovereign for outstanding public service and achievement.