The Duke and Duchess of Sussex welcomed their second child on Friday 4 June, announcing their daughter's birth and full name as Lilibet 'Lili' Diana Mountbatten-Windsor on Sunday.
While Prince Harry and Meghan's baby girl is eighth-in-line to the throne and she is unlikely to carry out royal duties when she is older, there are some guidelines when it comes to royal baby names.
READ: Princess Eugenie shares adorable first video of baby August playing with toy shark
WATCH: Harry and Meghan welcome baby daughter and name her Lilibet 'Lili' Diana
HELLO! takes a look at the traditions around royal baby names.
When is the royal baby name announced?
Typically, a royal baby's full name is not formally announced until around two to three days after his or her birth, as seen in the case of the Duchess of Cambridge's three children, but some royal parents choose to wait a little longer.
Princess Eugenie and Jack with baby August
Princess Eugenie and Jack Brooksbank announced their son's name August 11 days after his birth in February 2021, while back in 1988, the Duke and Duchess of York took two weeks to confirm Princess Beatrice's name. The Queen also didn't share Prince Charles' moniker publicly for a month after his birth in 1948.
The Queen has to approve the royal baby name
While this notion has never been confirmed directly by Buckingham Palace, it's widely understood that Her Majesty typically approves the names of those closest in line to the throne.
Royal parents usually share their children's chosen names with the Queen before any public announcement.
The royals choose traditional family names
Royals usually have three or four names, which are strong traditional names that have been used in the family for centuries, such as George and Charles.
Some royal parents have chosen to pay tribute to family members with their choice of middle names for their children.
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Princess Charlotte has the middle names Elizabeth and Diana
Many of the Queen's female children, grandchildren and great-grandchildren have the middle name Elizabeth, including the monarch's daughter, Princess Anne, as well as Zara Tindall, Lena Tindall, Princess Beatrice, Lady Louise Windsor, Princess Charlotte and Isla Phillips.
Princess Eugenie and Jack Brooksbank named their baby boy August Philip Hawke Brooksbank, while Zara and Mike Tindall called their son, Lucas Philip Tindall, both in honour of the late Duke of Edinburgh.
Harry and Meghan chose to name their son Archie Harrison, literally meaning the son of Harry, as his middle name, and the latest addition to the family, Lilibet, is in tribute to the Queen's family nickname.
Do the royals have a surname?
Members of the royal family traditionally don't use a surname; they are simply known by their first name in the public eye and His or Her Royal Highness.
They can also be known by the name of their house, such as Windsor, which may be different to their surname, such as Mountbatten-Windsor.
In 1947, Prince Philip of Greece was naturalised as a British citizen and became Philip Mountbatten instead while serving as a Lieutenant in the Royal Navy.
George and Charlotte use the surname Cambridge at school
The surname Mountbatten-Windsor has subsequently been given to descendants of the Queen and Prince Philip who are not future sovereigns, which is why Prince Charles doesn't have the surname himself.
According to the royal family's official website, it was 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".
At school, Prince George and Princess Charlotte are simply known as George Cambridge and Charlotte Cambridge to their school friends, in a nod to their parents' titles. This was also the case for Prince William and Prince Harry, who took on Prince Charles' title Wales as their surname at school.
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