When Diana got married to Prince Charles in 1981, the media always referred to her as Princess Diana, and that is how the world has always called her. But when Kate Middleton got married to Prince William, that wasn’t the case. That brings us to our question: is Kate a princess?
How is Middleton called
Catherine Elizabeth Middleton became Prince William’s wife in 2011. Since then, she is referred to in media as Duchess of Cambridge or Kate Middleton. She is a duchess. The day they got married, Queen Elizabeth II gave her and William the titles Duke and Duchess of Cambridge. Kate also adopted a female form of her husband’s noble title, and she is Her Royal Highness The Duchess Of Cambridge, Countess Of Strathearn and Lady Carrickfergus.
Princess rule
To be a princess, you must come from the royal family. Since Kate isn’t royal, she can’t be a princess. Princess Margaret can be a princess since she is a part of the royal family. She is the Queen’s sister. Her daughter is also a princess, Princess Anne, as well as queen’s grandkids, Princess Beatrice and Princess Eugene. The royal rule is that grandchildren born to the sons of the monarch receive the title of prince or princess, but not those born to the daughters of a monarch. That is the reason why Kate and William’s daughter Princess Charlotte is a princess, but her children won’t be.
Why was Diana a princess?
That is really something no one knows. Diana didn’t have royal blood, she came from a common family, just like Kate, and when she married Charles, she became Princess of Wales. After the divorce, she was simply Diana, but since the media and public always referred to her as Princess Diana, she stayed with that title to this day. Good Housekeeping stated that Kate Middleton will not be Her Royal Highness Catherine, Princess of Wales until Prince Charles takes the throne and William receives the title Prince of Wales. Then, when William becomes king Kate Middleton will be Her Majesty Queen Consort Catherine VI.
Source: Cheat Sheet