The Duke and Duchess of Cambridge's only daughter is currently styled as Her Royal Highness Princess Charlotte of Cambridge, but the six-year-old could be given another title in the future.
When Prince William becomes King, Charlotte could be named The Princess Royal, but that depends on a number of factors.
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The royal family shared facts on their social media accounts about Princess Anne's life in the lead-up to her 70th birthday on 15 August 2020. They tweeted at the time: "HRH The Princess Anne was named The Princess Royal, a title traditionally bestowed upon the eldest daughter of The Sovereign, in 1987. HRH is the seventh Princess Royal, following Princess Mary, the only daughter of King George V."
Despite being the eldest daughter of the sovereign George VI at the time, Princess Elizabeth was never known as the Princess Royal because her aunt Princess Mary was in possession of the title. Similarly, if Princess Anne is still using the title when her nephew William ascends the throne, he will not be able to bestow it upon his daughter Charlotte.
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Princess Anne is the current Princess Royal
Even then, the Princess Royal title is not automatically awarded to the eldest daughter of the sovereign. The Queen only bestowed the title of Princess Royal on Princess Anne in June 1987 even though it had been vacant since 1965, after the death of Princess Mary.
The title was first used in 1642 when Princess Mary, daughter of King Charles I and Queen Henrietta Maria, was made Princess Royal. Queen Henrietta Maria, who was the daughter of King Henry IV of France, is said to have wanted to imitate the way the eldest daughter of the French King was styled as "Madame Royale".
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