According to one expert daddy-to-be Prince William could name his little princess Diana, in loving memory of his mother.
Royal Author Phil Dampier said that he would be "astonished" if Kate and William did not use Princess Diana's name for their first-born, if they were to have a royal baby girl, the Mirror reported.
No sooner had the Duke and Duchess of Cambridge announced their exciting news, eager bookies offered odds on what the new offspring might be called.
Not surprisingly, topping the list of girls' titles was Her Majesty's namesake Elizabeth.
Bookies Ladbrokes had Liz chalked up as 8/1 favourite if the couple have a girl.
They also had William's dad Charles down as a joint favourite if Kate has a royal baby boy. Charles was 10/1, along with John.
Diana was the next most popular choice and Dampier believes the couple will no doubt be thinking about some sort of tribute to Princes William and Harry's late mother, who died in a car crash in Paris in 1997.
"I think Diana's influence will be very strong. Kate will surely have asked William about his upbringing and on their engagement Kate spoke about her regret at not meeting Diana and how she found her an inspiration," Dampier said.
"I'm sure she will be looking at what Diana did as a mother and learning from her. I would be utterly astonished if Diana didn't make up some part of the name should the baby be a girl".
"William missed her at the abbey when he wed Kate - she is always in his mind," he added.
Other popular names that might be chosen for the baby include Anne (12/1), James (12/1), Mary (14/1) and Richard (16/1).