With Britain celebrating a new royal baby Monday, many around the world have been asking what will Prince William and Kate Middleton name their first son. However, many since then have also realized they do not even know Prince William's surname, and so do not know what the newborn prince's surname would be.
Following the descendants of Queen Elizabeth II and Prince Philip, Prince William's surname is Mountbatten-Windsor, and that is also the name Catherine, Duchess of Cambridge – more commonly known as Kate Middleton - has taken too when she married Prince William.
On the official British Royal Family website, it explains that the Queen's descendants carry the surname Windsor and Mountbatten, to reflect her husband Prince Philip's surname.
The royal website also explains that the full surnames are not always used, but normally only when they are formally needed, for example at wedding ceremonies and crowning ceremonies.
However, what may interest many British royal fanatics is that while Prince William is currently officially recorded as a Mountbatten-Windsor in the marriage registry, he could later opt to choose a new name. But if he wants to do that he would have to wait until he is king, which might be a while. There are currently no suggestions that he plans to do this however.
The royal website explains, "Since a royal proclamation is not binding on succeeding rulers, King William could decide to add a name or two."
Prince William and Kate Middleton took the titles of Duke and Duchess of Cambridge when they married, and their newborn son, whose name has not yet been announced, has been born the Prince of Cambridge and is third in line to the British throne.
Here is a video of the birth of Prince William and Kate Middleton's baby being announced to the world at Buckingham Palace on Monday:
Here is a related video: