The Queen shared a touching tribute to celebrate her daughter Princess Anne's 71st birthday on Sunday.
A series of four images were posted on the royal family's Twitter account, showing the hardworking royal at various engagements over the years, including a sweet photograph of the Queen laughing and joking with her only daughter.
The caption read: "Wishing HRH The Princess Royal a happy birthday today."
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The royal family's official Instagram account also posted the same four photographs of Anne, encouraging their followers to learn more about her work, patronages and charities over the years.
Last year, three striking portraits were released by Buckingham Palace to mark the Princess Royal's 70th birthday.
The images taken at her Gloucestershire home, Gatcombe Park, showed Anne wearing a flowing pale-yellow dress by Maureen Baker, the same designer who created her wedding dress in 1973.
The Queen paid tribute to daughter Princess Anne on her birthday
The second was a close-up of the Princess wearing an emerald green outfit with one of her signature gold brooches, while the third showed her in off-duty country attire, posing in the woods on her estate.
It's not known whether Anne, who carries out hundreds of royal engagements each year, has joined the Queen at her Balmoral estate yet this summer.
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Princess Anne and Sir Tim on their wedding day in 1992
The Princess Royal shares two children, Peter Phillips and Zara Tindall, with her first husband, Captain Mark Phillips.
She went on to marry Vice Admiral Sir Timothy Laurence at Crathie Kirk near Balmoral Castle on 12 December 1992.
Anne welcomed her fifth grandchild earlier this year with the arrival of Mike and Zara's third child, Lucas, in March.
She is also grandmother to Zara and Mike's daughters, Mia, seven, and Lena, three, as well as Peter and his former wife Autumn's children, Savannah, ten, and Isla, nine.
The Queen with baby Anne in 1950
Princess Anne Elizabeth Alice Louise was born on 15 August 1950 at Clarence House, as the second child of the Queen and the late Duke of Edinburgh.
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She was educated at Benenden School in Kent and left with six GCE O-Levels and two A-Levels. She began to carry out royal engagements in 1969 at the age of 18 and she was the first member of the royal family to compete in the Olympics in Montreal in 1976.
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