ALTHOUGH ANYONE CAN suffer from insomnia, it's something which men are particularly competitive about. In their mistaken belief that insomnia is an interesting trait, male sufferers boast about how little they sleep at night, as if sleeping weren't the purpose of the exercise. So when I say that for reasons which are unclear to me, I've spent the last three nights awake until the first pale hint of dawn finds me exhausted and perspiring, but still with the heart-pounding alertness of a fugitive in hiding, I know many men will read it and say, "Now that's what I call a good night's rest". That's fine, pal. You win.

Now I am sharing a room - and on most nights a bed - with an 18-week-old baby, staying awake during the rare parts of the night in which sleep is possible seems particularly perverse. But even the interrupted nights are luxuriously long when you can't sleep. Instead of being woken by the screams of the other two children, I tend to them at the first whimper, glad to have something to do at 4am. I get no credit for this, because my wife only has my word for it that it happens, and she chooses not to believe me.

In the dark, my paranoia is fuelled by my inability to turn my thoughts to anything other than my wakefulness. I hear noises which I take to be intruders. I hear conversation in the street, and I imagine they're talking about me. "Tim is a jerk. Let's take his car." I put a pillow over my ears to block out the sound, and close my eyes tightly, hoping they'll stay shut of their own accord. When they open, I find myself nose to nose with a strange little man.

"I can't sleep," he says. My first thought is: You can't sleep?, but I resist the urge to be competitive about it, since it occurs to me I might just have been asleep. How else could my son have crept in here without me noticing, when I can hear the neighbours two doors down discussing my lack of fashion sense? As I take him back to bed, I tell him he mustn't be afraid of weird noises or the dark, but I'm not terribly convincing. He explains it's not noises but bad dreams, or fear of bad dreams, that keeps him awake. When I was his age my recurring giant alligator dreams induced a similar fear of sleep, but I decide this is not a good time to say so. I ask him what he is afraid his dreams will be about. "Being stolen," he says. Oh, cheers, I think. That should keep me awake for weeks.