It is a truism common to nearly all family gatherings that grandparents will frequently remark on how fast their beloved grandchildren seem to be growing up these days.
But now, instead of provoking a bout of eye-rolling at such platitudes, a new report seems to show the old folk were right all along: boys are indeed hitting puberty earlier than they used to.
The study by the American Academy of Paediatrics, first revealed by the New York Times, was published at the weekend. Widely seen as the best measure of the onset of puberty in American boys, it demonstrated they are showing signs of puberty six months to two years earlier than previously assumed.
The surprise finding builds on previous discoveries that appeared to show girls have also been developing faster.