From baby names to hair colour and birth date ... the announcement that the Duke and Duchess of Cambridge are expecting a second child may be mere moments old, but money has already begun to change hands over almost every conceivable aspect of the royal birth.
Bookmakers have described it as "the biggest novelty betting market of the year", with odds even being offered on the likelihood of the royals becoming new parents to triplets.
Although the due date has not been made public, William Hill have odds of 16/1 that the brother or sister to Prince George, who celebrated his first birthday in July, will be born on April 21 - the Queen's birthday.
The Duke of Cambridge said he and his wife were "thrilled" to be having a second child - but admitted Kate has had a "tricky week or so" after falling ill with severe morning sickness.
"She's feeling okay. It's been a tricky few days - week or so - but obviously we're basically thrilled, it's great news, and early days. We're hoping things settle down and she feels a bit better," he said.
Meanwhile, Paddy Power is offering 6/4 that the baby's hair will be brown, ahead of fair (5/2), red (3/1) or black (5/1).
Punters anticipating the royal household will swell by more than just one are being offered odds of 33/1 for twins and 250/1 for triplets.
A spokesman for the bookmaker said: "If there's one thing that baby George taught us it's that the public love a punt on a Royal offspring and we're bracing ourselves for another baby betting bonanza.
"Money is already pouring in by the pram-load and we expect this to be the biggest novelty betting market of the year."
Speculation also includes names for the baby. Current front-runners include regal favourites Elizabeth, Henry and Victoria at 10/1 with Paddy Power, and Alexander and James at 9/1 with William Hill.