Now that the Duchess of Cambridge is pregnant, all sorts of people have been presuming to predict how parenthood will be for the royal couple. David Cameron has assured the nation that they will make wonderful parents. Noel Gallagher, grumpy pop star and father of three, has warned the future king that he should get back into the army at once as it will be a lot more peaceful than being at home with a baby.

My bet is rather different. I suspect that Prince William will respond to fatherhood by feathering his nest at the taxpayers’ expense. Unlike the predictions made by Messrs Cameron and Gallagher – based on politeness and prejudice – mine is backed by solid research. In the current issue of Administrative Science Quarterly is a study showing that male bosses greet the birth of a child in a pretty elemental way: they give themselves a pay rise. And not only do they celebrate by paying themselves more, they pay everyone else less.

The study (which I first read about in the Economist) was carried out on a large sample of Danish chief executives and found that following the birth of a child the boss’s pay went up by an average of 4.9 per cent. Meanwhile their underlings were paid about 1 per cent less than had the CEO remained childless.