A post on Prince William and Kate's social media accounts showed a series of pictures of the monarch through the ages and heralded her for "inspiring a nation" and dedicating her life to service.
WATCH: The Queen's 70-year reign in 70 pictures
The Queen, who appears to have recovered after catching COVID a fortnight ago, reached 70 years on the throne last month – her Platinum Jubilee.
Alongside the images, the royal couple released a heartwarming tribute which read: "In this very special #PlatinumJubilee year, we celebrate Her Majesty The Queen and her historic 70 years of service on #IWD2022.
"Mother, grandmother, great-grandmother and Head of State, The Queen's extraordinary reign has been longer than any other monarch in British history - inspiring a nation and dedicating her life to the service of the Commonwealth and its people."
Prince William and Kate shared a series of pictures to honour the Queen
One of the portraits shows Prince William and Kate with the Queen at the Chelsea Flower Show in 2019, while another captured Her Majesty on a Silver Jubilee walkabout in 1977. A third photo saw Prince Charles kissing the Queen's hand at a polo match in 1988.
The post was echoed on Charles and the Duchess of Cornwall's Twitter account, including the photographs of the Prince with his mother and one of Camilla laughing with the Queen.
"In this very special #PlatinumJubilee year, we celebrate Her Majesty The Queen and her 70 historic years of service," their message read. "The Queen's extraordinary reign has been longer than any other monarch in British history and dedicated to the service of the Commonwealth and its people. #IWD."
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