Buckingham Palace announced on Friday that Prince Edward has been granted the title of Duke of Edinburgh, honouring the late Queen and Prince Philip's wishes.
Sophie, the former Countess of Wessex, is now the Duchess of Edinburgh and their 15-year-old son James, Viscount Severn is the new Earl of Wessex.
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However, there has been no change in title for Edward and Sophie's 19-year-old daughter, Lady Louise Windsor.
When Edward married Sophie Rhys-Jones in 1999, the couple were given the title of the Earl and Countess of Wessex, and Buckingham Palace said that their children "would have courtesy titles as sons or daughters of an earl," according to the BBC at the time.
Courtesy titles are only used by the peer's eldest living son, and the eldest son's eldest living son, and so forth. Other descendants are not permitted to use the peer's subsidiary titles.
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Edward and Sophie were made Earl and Countess of Wessex after their marriage in 1999
As a daughter of an Earl, Louise has been styled as Lady since her birth in 2003.
Similarly, this is why the daughters of Charles Spencer, 9th Earl Spencer, are Lady Kitty, Lady Amelia, Lady Eliza, Lady Lara and Lady Charlotte. Meanwhile, his eldest son is Louis Spencer, Viscount Althorp.
The Dukedom of Edinburgh – which in the past has been hereditary – will not, however, pass down to James when Edward dies.
James will become the Earl of Wessex and Forfar when the title of the Duke of Edinburgh reverts to the Crown, the Palace said.
James is now the Earl of Wessex
The news comes after the Duke and Duchess of Sussex decided to formally use their children Archie and Lilibet's royal titles – Prince and Princess of Sussex.
The rules set out by King George V in 1917 mean Archie and Lili, as the children of a son of a sovereign, are automatically a prince and a princess.
HELLO! exclusively revealed that King Charles agreed that the Duke of Sussex's children should use their royal titles at the end of 2022 - despite the fact that Harry and Meghan have stepped back as working royals.
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