The Princess Royal welcomed her fifth grandchild – and first grandson – last week when daughter Zara Tindall gave birth to her third child Lucas Philip Tindall.
But Princess Anne, 70, has another special occasion to commemorate on Monday as it's her granddaughter Isla Phillips' ninth birthday on 29 March.
Isla is the youngest daughter of Anne's son Peter Phillips and his estranged wife Autumn. The couple announced their decision to divorce last year, but Autumn has remained living on Anne's Gatcombe Park estate in Gloucestershire so that she and Peter can co-parent.
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Peter and Autumn have an eldest daughter, Savannah, who turned ten in December. Both Savannah and Isla were born at Gloucestershire Royal Hospital in 2010 and 2012 respectively.
While the children are not often pictured in public, they do join the Queen and the royal family on the balcony at Buckingham Palace, for occasions such as Trooping the Colour.
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Isla with mum Autumn, pictured in 2019
Savannah and Isla have also been spotted playing with their cousins Mia Tindall, seven, and two-year-old Lena Tindall, at the Gatcombe Horse Trials and they were given starring roles as bridesmaids at Princess Eugenie and Jack Brooksbank's wedding in October 2018.
Princess Anne made her first public appearance last Wednesday following the birth of her grandson Lucas on Sunday 21 March.
Isla pictured playing with cousin Mia Tindall in 2018
The royal paid a visit to the Greater Cambridge Shared Waste Service, where she met some of the area's waste and recycling collection crews.
Mike and Zara's baby boy is also the Queen and Prince Philip's tenth great-grandchild. A Buckingham Palace spokesman said in a statement: "The Queen and the Duke of Edinburgh are delighted with the news and look forward to meeting their 10th great-grandchild when circumstances allow."
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