kate middleton prince william
Kate Middleton and Prince William are expecting their third child.
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  • Kate Middleton and Prince William's royal baby is expected any day now.
  • The child's official title will likely be His Royal Highness Prince [Name] of the United Kingdom of Great Britain and Northern Ireland or Her Royal Highness Princess [Name] of the United Kingdom of Great Britain and Northern Ireland.
  • The child's everyday title will read slightly different.
  • Prince Harry and Meghan Markle's kids will not bear this royal title.
If you're a member of the British royal family, tradition is basically your middle name. So it should come as no surprise that as Prince William and Kate Middleton gear up for the arrival of baby number three, they're sure to stick to the royal rule book as far as titles go. 
While details on the name are scarce (OK, basically nonexistent), royal expert Marlene Koenig says we can count on one aspect of the kiddo's name to sound familiar. Koenig told Town & Countrythat according to royal tradition, the child's official title will either be His Royal Highness Prince [Name] of the United Kingdom of Great Britain and Northern Ireland, or Her Royal Highness Princess [Name] of the United Kingdom of Great Britain and Northern Ireland. Really flows off the tongue, doesn't it? 
But, since Prince William is also the Duke of Cambridge, the child's everyday title will read slightly different. Take, for instance, Prince George's birth certificate, which lists his full name as His Royal Highness Prince George Alexander Louis of Cambridge. 
Princess Charlotte's birth certificate uses the same royal nomenclature: Her Royal Highness Princess Charlotte Elizabeth Diana of Cambridge. 
For those wondering about Prince Harry and Meghan Markle's future kids, their titles will be completely different. Thanks to a royal rule called a Letters Patent passed by King George V in 1917 and Queen Elizabeth II's 2012 Letters Patent, Harry and Meg's kids will not enjoy the luxury of prince or princess titles. Instead, they'll be titled Lord or Lady [Name] Mountbatten-Windsor.