Kate Middleton is the Duchess of Cambridge, but in the future, she could inherit late Princess Diana's official title. When she was alive, the official title was Diana, Princess of Wales, and Prince Charles, who is the heir apparent to the British throne, is Charles, Prince of Wales.

So when Queen Elizabeth II dies and Charles becomes the king, the title of Prince of Wales might go to Prince William, who is currently the Duke of Cambridge. His wife, Kate will inherit the title of Princess of Wales, Express.co.uk reported.

Kate Middleton dress
Prince William and Kate MiddletonSIMON DAWSON/AFP/Getty Images

Diana became the Princess of Wales when she married the prince in 1981. Though following Charles' second marriage, his wife Camilla Parker Bowles got the title of Princess of Wales.

But due to its strong association with the late Diana, Camilla goes by the title Duchess of Cornwall, which is the feminine form of her husband's highest-ranking subsidiary title.

While there will be changes in William and Kate's titles after Charles become the king, it is highly unlikely that the title of Prince Harry, who is now the Duke of Sussex, will change.

Princess Diana and Prince Charles
Prince Charles and Princess Diana ride in an open carriage from Buckingham Palace to Westminster Abbey on July 23, 1986 for the royal wedding of the Duke of York and Sarah Ferguson in London.Reuters

The Prince of Wales title is given to the heir apparent to the British throne. Charles is reportedly the 21st person to hold the title. While it is expected to be passed on to his oldest, William, the younger prince, Harry will not be given the title.

In the line of succession, Harry is behind William and his kids Prince George, Princess Charlotte and Prince Louis.

Meghan Markle, Prince Harry., Queen
Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex during Trooping The Colour on the Mall on June 9, 2018 in London, England.Getty Images

Check out the royal line of succession below:

  1. Prince Charles, the Prince of Wales
  2. Prince William, the Duke of Cambridge
  3. Prince George of Cambridge
  4. Princess Charlotte of Cambridge
  5. Prince Louis of Cambridge
  6. Prince Harry, the Duke of Sussex
  7. Prince Andrew, the Duke of York
  8. Princess Beatrice of York
  9. Princess Eugenie of York
  10. Prince Edward, the Earl of Wessex
  11. James, Viscount Severn
  12. The Lady Louise Mountbatten-Windsor
  13. Princess Anne, the Princess Royal
Britain's Queen Elizabeth II (3L) stands with her husband Britain's Prince Philip, Duke of Edinburgh (3R), her son Britain's Prince Charles, Prince of Wales (2L) and his wife Britain's Camilla, Duchess of Cornwall (L), and her grandson Britain's Prince William, Duke of Cambridge (2R) and his wife Britain's Catherine, Duchess of CambridgeDOMINIC LIPINSKI/AFP/Getty Images