The Princess Royal cannot act in the King’s place if he is ill or overseas, despite the fact that her younger brother the Duke of York , and his eldest daughter Princess Beatrice can.
The only people who are able to act in the King’s place are the Queen Consort, the new Prince of Wales, the Dukes of Sussex and York, and Princess Beatrice.
Other than the Queen Consort, these individuals all have the role of Counsellor of State, which is a title that is automatically bestowed upon the four royals next in the line of succession who are older than 21.
Under Queen Elizabeth II, the new King Charles, as Prince of Wales, held this role. Despite being older than her brother Andrew, 72 year old Anne is lower down in the line of succession due to the archaic rule of male-preference primogeniture.This meant that even if the monarch’s eldest was a girl, if she had sons they would leapfrog their sister in the line of succession.
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