Buckingham Palace shared a rare photo of Prince Philip with the Queen to mark his 99th birthday

• The Queen's husband, Prince Philip, is celebrating his 99th birthday on Wednesday June 10.
• Buckingham Palace has released a new photo of the Duke of Edinburgh and the monarch in the grounds of Windsor Castle to mark the special milestone.
• The couple have rarely been photographed together since the duke retired from public life in 2017.

Buckingham Palace has shared a rare photo of the Duke of Edinburgh with Queen Elizabeth to mark his birthday.

Prince Philip is celebrating his 99th birthday on Wednesday, June 10 at Windsor Castle, where he has been living with the monarch since March.

The new photo was taken at the castle's quadrangle on June 1.

Her Majesty wore an Angela Kelly dress and and Cullinan V diamond brooch, while Philip wore a Household Division tie.

The couple have rarely been photographed together since the duke retired from public life in 2017. He was last seen publicly leaving a London hospital on Christmas Eve after being treated for a pre-existing condition.

Meanwhile, 94-year-old Queen Elizabeth has been pictured more frequently. Last week, the palace released photos of Her Majesty riding a horse in the grounds of Windsor Castle.

Prince Philip and the Queen met at a wedding when they were children. However, they didn't cross paths again until years later, when Philip was 18 and the then-Princess Elizabeth was 13.

They married in 1947, when Philip was 26 and the monarch was 21, and have been by eachothers' sides ever since.

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