A Bieber-haired youth knocked on the door last week, asking if my daughter was in. I gave him my best Kenneth Williams face – specifically, the one one above from Carry on Jack.

“She’s going out,” I replied. “Whom shall I say called?”

Bieber scuttled off on his scooter without answering (sans helmet, I noted – presumably to avoid squashing the coiffe.)

When I turned to go back into the house, my daughter was standing in the shadows of the corridor with that half-mortified, half-excited look of young love. Bieber, she informed me, was in fact called “Dean.” He was – is – her boyfriend.

I tried to affect the cool-parent nonchalance I had been practising for this eventuality, though I admit, I hadn’t expected to have to use it quite yet. Surely sixteen is the threshold for this kind of indecency? They’re ten.

And while they’re not exactly Rene and Renata (having observed them since, with my binoculars, from behind various bushes and playground furniture, they barely acknowledge each other – such is the complexity of young love) it struck me that this is the milestone that many blokes I know dread the most. Dad meets The Prospective Boyfriend is a well-worn comedy trope for a reason.

Mark died B was just three, so the only parenting milestones he bore witness to were of the first steps / ohmygodwhatdidsheeat,noYOUchangethefuckingnappy variety. How would he have coped this this one?

I’ve been mulling this over since. The answer is, I have no idea. My own response has surprised me. I had thought I’d be all Cressida from Viz’s Modern Parents strip, but in fact, I’ve gone more Cressida Dick from the Met – setting up a series of strategic command bases to check what they’re up to next.

Mark approached everything, even the most grotesque of nappies, with a playful, sidelong glance. How would he have approached the Bieber milestone?