Original article from Kent Live
When the birth of the newest addition to the Royal Family was announced, much of the attention was focused on first two names Prince Harry and Meghan Markle chose for their newborn child.
Lilibet was chosen to pay tribute to Her Majesty the Queen, who used it as a nickname from her childhood days when she mispronounced her own name.
And the second name Diana pays tribute to Prince Harry's mother Princess Diana, who tragically lost her life in a car crash in 1997.
But keen-eyed observers may have also noticed the somewhat unusual surname, Mountbatten-Windsor.
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While it has been used by all of the Queen's great grandchildren on their birth certificates, Prince William and Kate Middleton's children are understood not to use the name generally.
In April 2018, the couple welcomed Prince Louis. His birth certificate showed his surname as "His Royal Highness Prince Louis Arthur Charles of Cambridge."
It's thought they have the right not to, because Prince William and Kate represent the Royal Family officially, and therefore enjoy the status of His and Her Royal Highness.
As the Royal Family website states: "For the most part, members of the Royal Family who are entitled to the style and dignity of HRH Prince or Princess do not need a surname."
It means that Prince William and Kate instead decided for George and Charlotte to use the surname "Cambridge" when it was needed for things like school registration.
Meanwhile, due to Prince Harry and Meghan Markle's decision to move to the US and no longer represent the Royal Family at events, the palace announced they had lost their official status and accompanying privileges.
It means that, according to the Queen's official declaration, they will use the surname Mounbatten-Windsor for Archie and Lilibet instead of Sussex.
The Royal Family Website states: "In 1960, The Queen and The Duke of Edinburgh decided that they would like their own direct descendants to be distinguished from the rest of the Royal Family (without changing the name of the Royal House), as Windsor is the surname used by all the male and unmarried female descendants of George V.
"It was therefore declared in the Privy Council that The Queen's descendants, other than those with the style of Royal Highness and the title of Prince/Princess, or female descendants who marry, would carry the name of Mountbatten-Windsor."
Before 1917, members of the British Royal Family had no surname, but only the name of the house or dynasty to which they belonged.
In 1917, there was a radical change, when George V specifically adopted Windsor, not only as the name of the 'House' or dynasty, but also as the surname of his family.
It was changed as a result of anti-German feeling during the First World War, and the name Windsor was adopted after the Castle of the same name.
In 1960, The Queen and The Duke of Edinburgh decided that they would like their own direct descendants to be distinguished from the rest of the Royal Family.
At this point Mounbatten-Windsor was introduced to also reflect Prince Philip's surname.