When Sophie Wessex married into the Royal Family more than 20 years ago, some eyebrows were raised when she was not made a duchess.
Unlike her sister-in-law Camilla and her nephew's wife Kate, Sophie was given the title of Countess of Wessex when she tied the knot with Prince Edward in 1999.
Her title came as Edward was bestowed the name Earl of Wessex from his mother the Queen upon marriage.
However, the couple could both be set for changes to their Earl and Countess titles in future - but they will have to wait at least until Edward's older brother Prince Charles becomes King.
It was announced at the time of Edward and Sophie's wedding that he would one day succeed his father as the Duke of Edinburgh with the blessing of the late Prince Philip and the Queen.
If that happens, this, in turn, would make Sophie Duchess of Edinburgh - a courtesy title which was held by the Queen.
Sophie once told the Telegraph of the moment she and Edward were told Philip would like them to take on the title.
Love the royals? Sign up for the Mirror's daily newsletter to get all the latest news on the Queen, Charles, Kate, Wills, Meghan, Harry and the rest of The Firm. Click here to sign up.
She said: “We sat there slightly stunned. He literally came straight in and said, ‘Right. I’d like it very much if you would consider that’.”
The title of Duke of Edinburgh is currently held by Charles as he is the oldest child of Philip.
The title will revert to the Crown when Charles becomes King, meaning he is free to hand it out again.
However, it is not a given that Charles will automatically hand out the title to Edward and a report last year claimed the Prince of Wales might not give it to his youngest brother.
A source told the Sunday Times : "The prince is the Duke of Edinburgh as it stands, and it is up to him what happens to the title. It will not go to Edward.”
However, a Clarence House spokesman said at the time: “We do not comment on matters related to the accession.”
In a previous interview with the BBC, Edward noted how the final decision on the title remains with Charles.
He said: "It was fine in theory, ages ago when it was sort of a pipe dream of my father’s .... and of course, it will depend on whether or not the Prince of Wales, when he becomes king, whether he’ll do that, so we’ll wait and see."
