Kate Middleton isn't technically a princess — so why does her son's birth certificate say she is?

Prince Louis Arthur Charles of Cambridge’s birth certificate was released to the public on Tuesday — and there’s one detail that doesn’t make a lot of sense.

On the official document, the Duchess of Cambridge’s full name is written as Catherine Elizabeth Her Royal Highness The Duchess of Cambridge. And then, her occupation is listed as Princess of the United Kingdom.

Birth certificate
Prince Louis of Cambridge’s birth certificate was released a week after he was born. (Photo: PA)

Yet because only Queen Elizabeth’s children or grandchildren can be given such a royal title, it’s confusing as to why the Duchess of Cambridge (who, unlike Princess Diana, did not take on the title of princess) has been given one.

Birth certificate
The Duchess of Cambridge’s job occupation is apparently “princess.” (Photo: Getty Images)

However, according to royal commentator Richard Fitzwilliams, there’s a simple explanation. “When Prince William married Catherine Middleton they were granted the title of Duke and Duchess of Cambridge,” he explains. “William is HRH Prince William, Duke of Cambridge and so Kate, as his wife, is HRH The Duchess of Cambridge. If you marry a prince you become a princess. Louis’ birth certificate would naturally reflect this.”

Following the death of his father, Prince Charles, William will become King and Kate will be given a new title too.

The duchess will most likely be Queen Consort, as Queen Elizabeth’s mother was known when her husband, King George VI, became the monarch.

When Prince Harry and Meghan Markle wed on May 19, the couple are set to take on the titles of the Duke and Duchess of Sussex.

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