Royal Baby: This is the title Prince William and Kate Middleton's baby will have, and they'll technically be a commoner

Prince Harry is technically a commoner too

The new royal baby is due in April (Getty) (Getty Images)

With the newest royal expected to arrive in April, the Duchess of Cambridge is now officially on maternity leave, as she prepares for the arrival of her third child.

But although we don’t yet know whether a new prince or princess will be joining the family, we do know that Prince William and Kate’s third baby will be a commoner - despite what seems to be a pretty impressive title.

According to Town & Country, the newest addition to the royal family will either go by 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.

However, although the title sounds quite fancy, it turns out the baby will be considered a commoner in the eyes of the realm - despite being born to the Duke and Duchess of Cambridge and next in line to the throne behind Princess Charlotte.

Marlene Koenig, a royal historian, explained why. She told the magazine: “It sounds complicated, but in the UK, the only people who are not commoners are the Sovereign and peers of the realm, [those with titles such as] Duke, Marquess, Earl, Viscount, and Baron.”

But the good news is the title of commoner likely won’t last forever.

Just as the baby’s uncle Prince Harry is expected to leave the title of “commoner” behind once he marries Meghan Markle on May 19 2018, so too will the new Royal Highness of Cambridge when he or she gets a little older.

Until then, we are just excited that there will be a new royal baby, commoner or not.