Prince Harry and Meghan Markle's baby will probably have a different surname to the rest of the royals

• Members of the British royal family don't regularly use last names, but they do have a few to choose from in situations that require them.
• For example, as the son of the Duke and Duchess of Cambridge, Prince George uses Prince William and Kate Middleton's dukedom, Cambridge, as his last name at school.
• Prince Harry and Meghan Markle are the Duke and Duchess of Sussex.
• Therefore their first baby, who is due in 2019, will probably take on the surname Sussex.
• Harry and Markle's kids could also go by the hyphenated last name, Mountbatten-Windsor - which, technically, is the official surname for all descendants of Queen Elizabeth II and Prince Philip.

Meghan Markle and Prince Harry are expecting a baby early in 2019 - and it's likely their kids will go by a different surname than the rest of the British royal family.

While royals don't regularly use last names - they're easily recognizable without one - they do have a few to choose from in situations that require them, like when they're in school or in the military.

For example, as the son of the Duke and Duchess of Cambridge, Prince George uses Prince William and Kate Middleton's dukedom, or territorial designation, as his last name at school.

In place of his official title, "His Royal Highness Prince George of Cambridge," the 5-year-old is known by his classmates simply as George Cambridge. The name was even printed on his backpack when the young prince arrived for his first day at Thomas's Battersea in September 2017.

Similarly, Prince William and Prince Harry - whose father, Charles, is the Prince of Wales - went by William Wales and Harry Wales, respectively, when they served in the military.

If Harry and Markle, the Duke and Duchess of Sussex, continue this tradition, their children will take on the surname, Sussex.

Harry and Markle's kids could also go by the hyphenated last name, Mountbatten-Windsor - which, technically, is the official surname for all descendants of Queen Elizabeth II and Prince Philip.

Prince George is known as George Cambridge at school, as seen by the name printed on his backpack (right).

Back in 1960, the queen combined the royal family name of Windsor with Philip's surname from his maternal grandparents, Mountbatten, as a way to distinguish the couple's lineage from the rest of the British monarchy.

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