Nickname Princess Diana used to keep her relationship with King Charles a secret

Members of the Royal Family have hugely important official titles and styles that date back centuries, and it is no different today. But what you may not realise is that royals such as the Prince of Wales or the Duchess of Edinburgh don't just have one title – but several.
For example, the King's full and official title is: Charles III, by the Grace of God, of the United Kingdom of Great Britain and Northern Ireland and of his other realms and territories King, Head of the Commonwealth, […]
Nickname Princess Diana used to keep her relationship with King Charles a secret