I have this from The Telegraph, but have also seen similar stories all over the place, which leads me to believe that the wording comes straight from a press release or a courtier rather than something the media invented themselves.
Apparently, Buckingham Palace has announced that the child of the Duke and Duchess of Cambridge will be the first ever HRH Prince/Princess of Cambridge. Much in the same vein that the Duke was HRH Prince William of Wales after his father’s title and Princesses Beatrice and Eugenie are “of York,” no?
In the Mirror, a former mayor of Cambridge chimes in with: “There were some dukes of Cambridge but not a prince or princess.”
It seems both Buckingham Palace aides and royal journalists could do with a spot of royal history lessons.
Especially when one considers that Princess Mary Adelaide of Cambridge was mother of Queen Mary, and the great grandmother to Queen Elizabeth II – the same role Queen Elizabeth II will have to the unborn child.