Princess Anne has made history by becoming the first female member of the royal family to "stand guard" during the historic royal mourning tradition known as the Vigil of the Princes.
EXPLAINED: What is the Vigil of the Princes? Royals to carry out poignant tradition beside Queen's coffin
The Princess Royal, 72, joined her brothers Prince Edward and Prince Andrew, as well as the newly appointed King Charles III, at St Giles Cathedral in Edinburgh on Monday for the sombre occasion, taking their places by the Queen's coffin at 7.20pm. Anne was impeccably dressed in her military uniform to commemorate her late mother, who passed away last Thursday at the age of 96.
WATCH: King Charles leads his siblings at Vigil of the Princes
Princess Anne was dressed in the same Royal Navy ceremonial uniform that she had worn earlier in the day for the procession of the Queen's coffin in Edinburgh.
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The Princess, who is patron of the Royal Navy and Royal Marines Charity as well as being Commodore-in-Chief for Portsmouth, is also the only female member of the royal family to wear her uniform at state occasions.
The Princess Royal made history by taking part in the vigil
Although she hasn't actually served in the military like her brothers King Charles and Prince Andrew, she is an honorary Rear Admiral.
She carries out hundreds of engagements with her military patronages and affiliations every year and usually tops the hardest working royal list.
The Vigil of the Princes is a long-standing tradition, honoured ever since the death of King George V in 1936, and was last carried out during the Queen Mother's funeral in 2002.
Princess Anne arrived for the vigil with her brothers
The late Queen will lie in state at St Giles Cathedral for 24 hours. Members of the public will be able to view the Queen's coffin at the cathedral and pay their respects from 5pm for a period of 24 hours.
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On Tuesday, Princess Anne will be accompanying the Queen's coffin when it is flown to London by RAF aircraft to RAF Northolt. The coffin will then be taken to rest at Buckingham Palace's Bow Room.
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