Diana, Elizabeth and Grace have been the favourites for a royal baby name ever since Meghan Markle and Prince Harry announced they were expecting.
But now there is a late guess which bookies seem convinced could be the one, and they've just slashed the odds from 100/1 to 20/1.
Allegra is an Italian girls name which means joyful and lively.
It is reportedly one of the names Harry's mum Diana wanted if she had a girl.
A huge gamble this morning caused bookies to slash the odds, the biggest move Ladbrokes has made since betting on the baby opened last year.
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Alex Apati, of Ladbrokes, said: "It's probably the most bizarre eleventh hour move we could've seen, but the money is coming in thick and fast for Allegra.
"We wouldn't be surprised to see the name right up there with the frontrunners by the time the birth gets announced."
But it's still not as popular as some of the other choices, with Diana and Grace in the top spot at 6/1 followed by Elizabeth at 8/1.
Arthur is in the top boys spot at 8/1 followed by Philip at 10/1 and James as 12/1.
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Meghan is due to give birth any day now, with fans on the lookout for any hint of clue that the time has finally arrived.
Earlier today people got very excited when a police escort was spotted in between London and Windsor.
Witnesses saw a number of cars rushing through Chiswick.
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A source told OK! Online : "This morning we saw a load of cars being given a police escort through Chiswick.
"It could be a politician or something else but that’s the route Meghan would take if she had to go to hospital from her home, so naturally we thought it was her."
