A staggering £1 million has been staked on bets about naming the Royal baby, with George and Alexandra emerging as the hot favourites.
Other strong contenders for the Duke and Duchess of Cambridge's baby include Elizabeth, Diana, Charles and Philip.
Kate and William are also likely to take inspiration from Kate's side of the family, possibly honouring her father Michael, or picking Francis, which is both her father and her grandfather's middle name.
Frances was the Duchess of Cambridge's great-great-great grandmother's first name, and was also William's mother Diana's middle name and his grandmother Frances Shand-Kyd's name.
Meanwhile James, another very strong favourite if the baby is a boy, has links to both families. Kate's brother is called James.
The royal baby will initially have a hospital bracelet with the name 'baby Cambridge.' Prince Harry's name was announced on the same day of his birth announcement, Prince William's name took a few days of decision making and Prince Charles's name was not made public for more than a month after he was born.
Bookmakers also said punters were expecting the baby to be a girl, with odds of around 6 -1, weighing between 7lb-7lbs 15oz, and to have brown hair.
Once the baby is born the Queen will be informed of the chosen names before they are announced officially, but she is unlikely to exercise her veto.
Royal writer Christopher Warwick said: "The Queen is so down to earth that she's not likely to jump up and down and say this boy has got to be called Charles and George.
"This isn't going to be 'Granny, do you approve?' but more 'These are the names we've chosen - do you like them?'.
"It's much more of a personal thing these days."
TOP 10 NAMES IF IT'S A GIRL....
1) Alexandra (9/4)
2) Charlotte (5/1)
3) Elizabeth (10/1)
4) Victoria (10/1)
5) Isabella (12/1)
6) Diana (14/1)
7) Alice (20/1)
8) Mary (25/1)
9) Catherine/Kate (33/1)
10) Grace (33/1)
TOP 10 NAMES IF IT'S A BOY...
1) George (5/1)
2) James (10/1)
3) Henry (14/1)
4) Arthur (20/1)
5) Louis (25/1)
6) Albert (40/1)
7) Alexander (40/1)
8) Benjamin (40/1)
9) David (40/1)
10) Philip (40/1)
(source: William Hill)