Prince William and Kate posted a photo of Camilla wearing a chic navy blazer and polka dot skirt on their Instagram Stories.
The royal couple captioned the image "Wishing the Duchess of Cornwall a very happy birthday today!" followed by a balloon emoji.
WATCH: Prince Charles and Duchess Camilla's garden is another world
She has two children from her first marriage to Andrew Parker Bowles; Tom Parker Bowles and Laura Lopes.
Kate and William shared this message on Instagram
Laura's daughter, Eliza, had a starring role as a bridesmaid at William and Kate's royal wedding in 2011 when she was just three.
Camilla has five grandchildren in total, with Laura also a parent to twins, Gus and Louis, while Tom has two children, Lola and Freddy.
The royals at the G7 Summit in June
Meanwhile, the Prince of Wales is a grandfather to William and Kate's three children, Prince George, seven, Princess Charlotte, six, and three-year-old Prince Louis, as well as the Duke and Duchess of Sussex's children, Archie, two, and one-month-old Lilibet.
Charles, Camilla, William and Kate were last pictured together publicly with the Queen at the G7 Summit in Cornwall in June.
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