London-based bookmaker William Hill have already come up with the following odds on the baby's likely name: Alice: 8/1, Elizabeth 10/1, James 12/1 and Arthur 12/1. The likelihood of a boy or a girl is being predicted as equal - always good news for fans of scientific accuracy - with the likelihood of Kate having twins at an exciting 33/1.
Traditionalists will be pleased to discover that the experts are favouring a return of names long popular in the royal family, with some recent favourites getting a nod. Diana is currently at 16/1 odds, Margaret is 20/1 and the odds of Charles getting a nod are 25/1.
Competitor bookmaker Ladbrokes gave Alice top ranking (7/1), then Arthur at 10/1, Victoria at 10/1, Alexandra at 12/1, Albert at 14/1 and, in a nod to great grandpa, Phillip at 14/1.
"The early money suggests punters would love to see Kate and Wills welcome another little girl into their family, who is called Alice," said Ladbrokes' Jessica Bridge. "It should come as no surprise to see fairly normal yet regal names top the betting."
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