Just when you thought the Queen couldn't possibly have more cause for celebration, she's gone and reached another milestone.

Queen Elizabeth II has just become the first British monarch in history to celebrate a Sapphire Jubilee, marking 65 years since she took the crown.

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On 6 February 1952, at the age of 25, Elizabeth acceded the throne after her father King George VI died in his sleep at Sandringham House in Norfolk, England.

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Credit: ASSOCIATED PRESS

She made history in 2015 when she became the longest-reigning monarch in British history, and again in 2016 when she became the world's longest-reigning living monarch.While this historic event is certainly cause for celebration, it also marks 65 years since the death of her father.

There are no official engagements planned. The Queen will spend the day at Sandringham House, where he father died.

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