Princess Eugenie's official title when she marries Jack Brooksbank

What's in a name? Well, when it comes to the British Royal Family, quite a lot.

We know that following her marriage to Prince Harry earlier this year, former Suits star Meghan Markle became Meghan, Duchess of Sussex, giving up the 'Markle' name for an official royal title.

So what will happen to Princess Eugenie’s title when she weds Jack Brooksbank today?

According to royal historian Marlene Koenig, the decision is entirely up to her.

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Following the nuptials at Windsor Castle, Princess Eugenie can decide to remain Her Royal Highness, Princess Eugenie of York, or choose to be formally addressed as Her Royal Highness, Princess Eugenie, Mrs. Jack Brooksbank.

The Princess can also choose to renounce her royal title altogether and become Lady Eugenie.

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The options are not so boundless when it comes to her fiancé's official title, however.

Tradition in the British monarchy indicates that while wives of male heirs (such as Meghan Markle and Catherine Middleton) receive official titles, husbands of female heirs do not—meaning Brooksbank will likely remain Mr. Jack Brooksbank.  

"There is no precedent for giving a peerage to the commoner husband of a princess on the wedding day," explained Koenig.

As for what Princess Eugenie decides, we're waiting with bated breath to find out.