Prince William made his mum Princess Diana a heartbreaking promise just one year before she died in a fatal car crash.
The Duke of Cambridge, who was just 14 at the time, vowed to give his mum back her title of Her Royal Highness which she was stripped of during her messy divorce from Prince Charles.
After marrying Charles in a fairytale wedding at St Paul's Cathedral in 1981, Diana became HRH The Princess of Wales.
But in 1996, almost a year after she infamously said there were "three of us" in her marriage to Charles, in reference to his love for Camilla in the tell-all BBC Panorama interview, the pair divorced - and Diana said goodbye to her HRH.
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While the Queen was happy for Diana to keep her HRH because she was mother to the future King, Charles reportedly insisted they were removed.
Diana was then known only as Diana, Princess of Wales.
The loss of her title meant friends or staff were no longer required to bow or curtsey in her presence, but she would now have to curtsy to her former husband, her sons and other royals.
This led to a heartbreaking conversation between Diana and a then 14-year-old Prince William.
In his book 'A Royal Duty', Diana’s butler and friend Paul Burrell claimed William promised to restore her title.
The young prince reportedly told his mum: "Don’t worry Mummy, I will give it back to you one day when I am King."
Mr Burrell claims the conversation left Diana in tears.
However, William’s promise was sadly left unfulfilled as his mother died in a car crash almost exactly a year to the day of the divorce, on August 31, 1997. Her companion Dodi Fayed also died.
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