Whatever you do, don't call her "Your Majesty."
While many Americans may equate this term with any sort of royalty, it's actually quite a specific title – meant only for the Queen.
So when Kate Middleton
becomes a princess on April 29
, the proper way to refer to her will be Her Royal Highness, or HRH – a "style" that commonly precedes the names of princes and princesses in the British Monarchy.
And speaking of names, Kate's is about to become a whole lot longer.
When the couple is married, Prince William
will probably be bestowed a Dukedom (possibly Cambridge or Sussex), which would make Kate a duchess in addition to a princess.
"She would [still] be a princess because she's married to a prince," explains Clive Cheesman from the College of Arms. "But she'd normally be referred to as HRH The Duchess of Cambridge." Or, less formally, "Princess Catherine, Duchess of Cambridge."
Royal dukedoms are seen as a way to make the title of "prince" a bit less visible. But just as Kate will still be a princess either way, if William gets a dukedom, he would also remain a prince.
If, however, William does not get a new title – which is a possibility – Kate would take his
name. In that case, "formally, she would be HRH Princess William of Wales," says Cheesman. Informally, she would be referred to simply as Princess Catherine.
"You hear informal uses more these days," notes Cheesman. "But the formal use would still be there and used in many circumstances."
Here's hoping she registers for some new stationary!
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