Buckingham Palace released a sweet new portrait of the monarch, 94, and her husband, 99, sitting in the Oak Room at Windsor Castle, as they beam at the colourful card made by their great-grandchildren, Prince George, Princess Charlotte and Prince Louis.
WATCH: The Queen and Prince Philip's love story
The gift is emblazoned with the number 73, coloured in neatly by the three royal youngsters, surrounded by colourful polka dots.
Prince William and Kate wrote in their tweet alongside the close-up of the homemade card: "Wishing a very happy wedding anniversary to Her Majesty The Queen and His Royal Highness The Duke of Edinburgh!"
George, Charlotte and Louis' handmade card
In the new photograph, taken by royal photographer Chris Jackson, the Queen is wearing a pale blue double wool crepe dress by Stewart Parvin and a chrysanthemum brooch made from sapphires and diamonds set in platinum, while Philip wears a blazer, shirt, tie and trousers.
Then Princess Elizabeth wore the brooch in images taken on her honeymoon in Broadlands in Hampshire in 1947, and again in pictures released to mark her 60th wedding anniversary in 2007.
The new portrait of the Queen and Prince Philip. Credit: Chris Jackson/Getty
Elizabeth and Philip tied the knot at Westminster Abbey on 20 November 1947. The Princess wore a white satin and embroidered wedding dress designed by Sir Norman Hartnell, accessorising with Queen Mary's diamond fringe tiara, which was loaned to her granddaughter Princess Beatrice for her nuptials to Edoardo Mapelli Mozzi in July.
The Queen and the Duke have been residing at Windsor Castle during England's second lockdown, having also stayed together at the Berkshire palace during the first national lockdown in March.
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