Not since the birth of Prince George in 2013 has a royal baby been so eagerly anticipated.

But while Prince Harry and Meghan Markle’s baby is set to be the most famous newborn of 2019, their child will have a decidedly less important title than their cousins unless a major family shake-up occurs between now and the birth.

According to the Letters Patent issued by King George V in 1917, only the grandchildren of a monarch or those in direct line to the throne can be styled as a prince or princess.

“The grandchildren of the sons of any such Sovereign in the direct male line (save only the eldest living son of the eldest son of the Prince of Wales) shall have and enjoy in all occasions the style and title enjoyed by the children of Dukes of these Our Realms,” the decree states, according to Good Housekeeping.

This means that the great-grandchildren of the monarch do not automatically receive HRH titles except for Prince Charles’s oldest grandson, Prince George.

As a result, the Duke and Duchess of Sussex’s offspring will be known as either Lady or Lord Mountbatten-Windsor unless one of two things occurs before their first child’s birth.