London - When Kate, the duchess of Cambridge and wife of Britain's Prince William, names a ship on Thursday in Portsmouth, it may be the last chance the public gets to see her before she goes on unofficial maternity leave.
The pregnant duchess, often credited with having injected fresh life - now literally as well as metaphorically - into the royal family, is rumoured to be due on 13 July, though Buckingham Palace has refused to confirm a date.
She may attend the Queen's official birthday parade, Trooping the Colour, on Saturday, and a Garter Day service at Windsor Castle on Monday, but those appearances have not been confirmed.
Prince William is determined to throw a "Kremlin-like security net" around the birth, just as he did at their much-hyped wedding two years ago, according to royal biographer Hugo Vickers.
That means the baby may be something of a "one-day wonder", he says, as the public will see little apart from the duchess being whisked into hospital when she goes into labour and her later reemergence with a tiny bundle.
Bookmakers are taking bets
That has not stopped the tide of baby-related gossip and speculation.
Bookmakers are taking bets on just about everything, from whether it will be delivered by Caesarian section to which celebrity magazine will get the first pictures - the favourite in that race is OK!.
Paddy Power paid out on bets that it is a girl as early as March, when the duchess reportedly made a swiftly curtailed reference to her "d..." as she accepted a teddy bear from a wellwisher.
Topping the list of fancied names is Alexandra, according to Paddy Power spokesperson Rory Scott, who suspects there may have been some kind of leak. "We suddenly saw a lot of bets on that and it's not a hugely traditional name, nowhere near the top 10 at the start."
Since royal babies can have a multitude of appellations, royal watchers are also guessing that Elizabeth and Diana may be among them, or Charles and Philip if the baby defies the bookmakers' odds and turns out to be a boy.
"They're quite likely to respect the immediate ancestors of the baby," says Vickers: a traditional name is likely. However, he adds, "with Prince William you can't be certain of anything, he does his own thing".
The Cambridges are set to be thoroughly modern parents.
The duke is likely to be present at the birth - his father Prince Charles was the first royal father to do so - and is also reportedly to take two weeks of paternity leave from his job as a search and rescue pilot in Wales.
Royal gossips claim Kate is introducing an even newer royal tradition by having a baby shower, courtesy of her younger sister, party girl Pippa Middleton. Her brother James Middleton, who has set up a cake company, is to bake a cake in the shape of a pacifier.
The duchess is expected to give birth either at the same hospital where Princess Diana gave birth to William, St Mary's in London, or at the Royal Berkshire Hospital in Reading, where she herself was born, should she go into labour at her parents' rural home in Bucklebury.
Afterwards, she is to spend the first six weeks at her parents', her uncle Gary Goldsmith let slip to the Daily Telegraph, rather than returning to the formality of Kensington Palace.
The baby itself is heralding a new age of royal gender equality, as he or she is set to accede to the throne regardless of the sex.
Three direct heirs
A succession law passed by parliament getting rid of male primogeniture received royal assent in April, though it still has to be approved in all 15 Commonwealth countries where Queen Elizabeth II is head of state.
For the queen, the birth and the cementing of her dynasty with three direct heirs means a great deal, says royal biographer Sarah Bradford.
After a period in the 1980s and 90s when the monarchy was hit by scandal and tragedy, including what was seen as the queen's heartless response to the death of Diana, the monarch has appeared "tremendously happy" over the past two years, Bradford says.
Around 2 billion people witnessed the marriage of William and Kate in 2011 - Britain's royals are still "frightfully good at spectaculars", says Bradford - and last year the queen celebrated her Diamond Jubilee to much popular approval.
And so the first baby to be born directly in line to the throne in 30 years is due to arrive at a time when the monarchy has rarely appeared so scandal-free, glamourous or in touch with public opinion.
As Bradford puts it: They have reached a point which is "utterly desirable".