Catherine last week showed signs of a fuller face, while her haircut, days earlier, triggered talk of a baby.
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As a country - and swath of the world - goes into foetal meltdown over the news that Kate and William are expecting, a distinct unwritten protocol has been broken with the announcement of the pregnancy at just two months.
It's common, with very good medical reason, to hold pregnancy news until 12 weeks. As many as one in four pregnancies ends in miscarriage and sharing news too soon can be a painful and salutary lesson.
The Duchess' condition, requiring hospitalisation and a period of rest thereafter, is necessarily going to mean a different approach to that of royal mothers in the past. Diana suffered from morning sickness but was required to maintain duties throughout.
The official announcement from St James' Palace said "As the pregnancy is in its very early stages, Her Royal Highness is expected to stay in hospital for several days and will require a period of rest thereafter."
Catherine, in a post-Leveson world, will be given space and allowed to rest as much as is possible in a social-media-heavy, news-hungry internet era. But hiding the pregnancy was always going to be hard.
Indeed, as much as the traditional 12-week watershed has been broken, the announcement may not have come a day too soon - from the cleverly distracting haircut to the outfit choices, not to mention the clear signs of extra weight around the Duchess' face, many an onlooker has speculated in recent weeks as to the pitter-patter of royal feet.
The couple's Asia tour saw Kate drinking water and sporting dresses that seemed to show signs of a baby bump - an early call, as it turns out.
Had the family waited until the traditional time to make the announcement, the baby would have been an uncannily neatly-timed Christmas gift to the Queen and her subjects. As it is, waiting until the end of 2012 has given Elizabeth II close to a year to bask in the Jubilee spotlight.
As commentators in London have underlined, and shall do so many times more over the next seven months, this pregnancy is both a private and intensely public affair, and will be played out under the gaze of the world.
Just six hours after the news broke and Twitter has exploded with #royalbaby comments. Mock-ups have mushroomed across the internet showing images of the child at five years of age - yes, really - and calls are already being made on social media for a 'No Royal Baby' option on the Guardian newspaper's site (following the success of their 'No Olympics' coverage option).
For the stauncher republicans out there, maintaining foetal humbug status will take effort. Predictably, the baby's even tweeting (@royalfetus and many others), while the news has triggered chat of a potential baby boom. To those who are due to give birth in 2013, has the thought crossed your mind that your son or daughter could be in line to become a royal partner? You're not alone.
Some are even aflutter as to the heir's horoscope. The baby's birthday has been pegged by Glamour magazine at August 27, a date that would mean the third-in-line to the throne would be a Virgo: Modest and shy, meticulous and reliable, practical and diligent, intelligent and analaytical. One the dark side - even Wills and Kate's offspring may have impefections - they may be fussy and a worrier, perfectionist and conservative, over-critical and harsh.
And all this in the very early stages of pregnancy, well within the zone that expecting mothers are usually encouraged to keep mum.