What utterly wonderful news. You must be thrilled! Naturally the whole nation is chuffed for you. The letters of congratulation will come flooding in, the emails, tweets, royal Facebook messages with special elbow length white gloves, and so on. And deservedly so: even rascal republicans like me take delight in that most simple and superior of joys, the arrival of a new life on Earth, and find ourselves smiling at your blissful news.
In particular, I do hope that news of acute morning sickness is a passing rather than permanent concern.
Your imminent parenthood is of course the perfect moment for you to renounce the luxuries of royal patronage and aristocracy, in favour of the middle-class normality that most of your fellow compatriots enjoy. Forgive me if I offer a few starting points.
First, lose the titles. Neither of you have a special claim on the glorious city of Cambridge, so quit pretending that you do.
Second, give the gorgeous little issue of your love a plainly English name. Larry, for instance, or Louise; not Marmaduke or Petronella.
Third, send the little prince or princess to a normal school. Not necessarily a bog standard comprehensive; grammar school would be fine, but better still would be any old city academy.
Fourth, get a decent suburban townhouse to raise your family in, rather than a vast palace which will merely articulate his or her distance from the people he or she will serve.
Fifth and finally, at all costs don't let Uncle Harry buy your kid a ticket to Las Vegas.
If you do these things, I should think everyone will be a winner. Your baby will thank you for the life of relative freedom you've bestowed. Your own lives will be free of all those press trips to random Pacific islands that you don't really enjoy. And above all, we'll have a royal family that actually bears some resemblance to the people of this country.
But tut tut, I hear you say. Now is not the time for republicans to harp on about such antediluvian nonsense as "democracy" or "people power". On the contrary, I think now is precisely the time for us to restate our case, which I'll do in another letter to you soon.
For now, heartiest congratulations on your lovely news, and very best wishes for the anxious, thrilling, and ultimately joyful time to come. Even those of us who think your public role a total fraud shall raise a glass to you this evening. We wish you well.