The Duke and Duchess of Edinburgh's son, James, Earl of Wessex, celebrated his 16th birthday on Sunday.
While James and his older sister, Lady Louise Windsor, are not expected to carry out royal duties once they have completed their education, James's birth sparked a new royal tradition.
Prince Edward and Sophie welcomed their son on 17 December 2007 at Frimley Park Hospital in Surrey.
Four months later, he was baptised in the private chapel of Windsor Castle and he was the first royal baby to wear a replica of the original royal christening gown.
The Honiton and lace gown dated back to 1841 when it was created for Victoria, Princess Royal's christening. It was used by the royal family until 2004, by which point it had been worn by 62 royal children, including King Charles and his sons, Prince William and Prince Harry.
Lady Louise was the last royal baby to wear the original christening gown. It had become too delicate so the late Queen Elizabeth II commissioned her personal wardrobe advisor, Angela Kelly, to create a replica.
Princess Beatrice and Edoardo Mapelli Mozzi's daughter, Sienna, was the last baby to wear the newer gown for her christening in April 2022.
Lady Louise and James are growing up out of the public eye, although they have attended some major royal events in recent years, including Trooping the Colour, the late Queen Elizabeth II's Platinum Jubilee celebrations and King Charles's coronation.
The siblings also guarded their late grandmother Queen Elizabeth II's coffin during a moving vigil when she was lying in state at Westminster Hall days before her funeral in September 2022.
They joined their cousins, Prince William, Prince Harry, Princess Beatrice, Princess Eugenie, Zara Tindall and Peter Phillips.
Lady Louise is currently studying English at St Andrews university in Scotland, while James is in the final year of his secondary education and will sit his GCSEs next spring.
James was previously known as Viscount Severn, but following the change in his parents' royal titles from the Earl and Countess of Wessex to the Duke and Duchess of Edinburgh in March 2023, he took on his father's former title.
The dukedom – which in the past has been hereditary – will not, however, pass down to the Edinburghs’ son James when Edward dies.
Viscount Severn will become the Earl of Wessex and Forfar when the title of The Duke of Edinburgh reverts to the Crown, the Palace said.
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