Although Buckingham Palace has never confirmed the exact date, Saturday is rumored to be the official due date for the child who will become the third in line to the British throne.
"There are really only two questions: boy or girl? And, what's the name?" Robert Hardman, a reporter with The Daily Mail, tells NPR's Weekend Edition Saturday.
A recent change in the law of royal succession means that for the first time, if Kate and William's first child is a girl, she will keep her place in line for the throne even if a future brother comes along.
Hardman, who spoke to host Scott Simon, says Elizabeth and George are top picks for British punters. If it's a girl, Elizabeth would honor the current monarch, he says. If, on the other hand, the duke and duchess of Cambridge leave St. Mary's Hospital in Paddington with a boy, "George VII would have a nice ring to it," he says.
But if you're hoping to be the first with the news of the royal bundle, don't bother monitoring the palace Twitter feed, Hardman says.
Instead, the tip that the joyous event has occurred will be when a member of the royal household emerges from the hospital clutching a red folder with a piece of paper containing the name, if one's been chosen. Next, they will be driven to Buckingham Palace.
Once there, "the piece of paper will be taken inside, placed in a silver photo frame, on a wooden easel and brought outside the palace and put on display for the world to see," Hardman says.
"There are some things that can still beat Twitter. [Like] an old-fashioned wooden easel," he says.
SCOTT SIMON, HOST:
This is WEEKEND EDITION from NPR News. I'm Scott Simon. We've got well-publicized births in the United States, of course - like Kanye West and Kim Kardashian's new, little empress, baby North West. But in Britain, the baby that's so breathlessly awaited could well be a future monarch.
Kate Middleton and Prince William are expecting their first child. It has been rumored, but not confirmed by the Palace, that the due date is today. The baby will be third in line to the throne.
We called up Robert Hardman, of the Daily Mail newspaper. Thank you very much for being with us, Robert.
ROBERT HARDMAN: How are you, Scott?
SIMON: Now, help us understand what's going on now. I mean, are antimonarchists just sort of being quiet about this?
HARDMAN: Yeah. They more or less decided to go on vacation. The whole country is on a sort of state of standby excitement. A handful of Republicans are keeping well out of the way, and everyone else is just waiting with really, two questions: Boy or girl? And what's the name?
SIMON: Well, before we get to that, there's a new piece of legislation we ought to talk about, about gender and the lineage to the throne.
HARDMAN: Yeah. This baby, be it a boy or a girl, will really herald in an entirely new era in the 1,000-year history of the monarchy because for the first time, this will be a truly equal child. There's been a piece of legislation here called the Succession to the Crown Act, which involves amending lots of very ancient, old laws. But what it effectively means is that if it's a girl, she won't be superseded by a younger brother.
Historically, boys always came first - which was extremely unfair, but that's the way it was. It meant that actually, out of the 40 monarchs we've had since 1066, only six have actually been queens. They've been very good queens, on the whole.
SIMON: I was going to point out, some of the most imposing monarchial figures, and greatest historical figures in Britain, have been queens.
HARDMAN: Absolutely. I think you asked anybody to list their top monarchs, I think they'd say Queen Victoria or Elizabeth I, and Elizabeth II would be right up there at the top. So really, what we're looking at is a very - sort of 21st century royal pecking order. The laws of succession have changed, and this child will be the first beneficiary.
SIMON: The betting parlors have pools, I gather, on what the name might be.
HARDMAN: It's almost certainly going to be something royal, and probably something new. I don't think if it is a girl, for example, you wouldn't really want to saddle a poor little baby with a name like Victoria. I mean, talk about the burden of expectation. Not to mention when the poor thing hits her teens, every time she's seen doing something she shouldn't there'll be sort of headlines saying, you know, what about Victorian values?
So I think probably not Victoria. I'm sure Elizabeth might well be in there somewhere.
HARDMAN: As a tribute to the current queen, if it is a girl. If it's a boy, the bookmakers, the people running the gambling, they reckon George is probably out in front.
HARDMAN: George is a popular name.
SIMON: We have a bad history with King Georges on this side of the pond, you know.
HARDMAN: Yeah. There was a George who actually was our second-longest lived monarch. But you need no lessons about him. But more recent Georges - George V, of course, created the House of Windsor; George VI, our current queen's father, much loved, heroic, wartime leader. So we like our Georges. We like our Georgian architecture. So George VII might have a nice ring to it. But who can tell?
SIMON: Mm-hmm. Do you expect Klaxon horns to go off at the moment of birth?
HARDMAN: I expect...
SIMON: Or maybe not at the moment, at the moment they announce the birth.
HARDMAN: I think it's more likely there will be sort of Keystone Cops, really, because they've decided there is no - they're not going to announce this by the Internet, by Twitter, by email; anything like this. They're going to stick to the old- fashioned way. So at a given point, a member of the royal household will emerge from a hospital clutching a red folder, which will have in it the details of the birth and the name - if there is one, at this stage - and will then get in a car, drive from the hospital to Buckingham Palace. Then when they get to Buckingham Palace, the piece of paper will be taken inside, placed in a silver photo frame, put on an easel, and then brought out and placed in front of the palace for the world to see. And at that point, and that point only, we'll actually know.
HARDMAN: We will know and say, that's the moment when we're all put out of our guessing game.
SIMON: Oh, my gosh. They do know how to put on a show, don't they?
HARDMAN: They do. I think it's really - I rather like the sort of theater; and here we are in the 21st century, and there are some things that can still beat Twitter - a nice, old-fashioned, wooden easel. For traditionalists, I think this is a great victory.
SIMON: Robert Hardman, who writes for the Daily Mail, is also author of a book that's just been published in the United States called "Her Majesty"; speaking from London. Robert, thanks for being with us.
HARDMAN: Thank you very much, Scott.
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