There's a famous photograph of John F Kennedy in the Oval Office: the world's most powerful man at work while his infant son plays under the desk. It's a charming picture from a bygone age. In the early 1960s, desks still did not have personal computers. And the reason President Kennedy could look so relaxed was that there was no risk of the child pressing his PC's off-switch in the middle of an important e-mail to Krushchev about the Cuban missile crisis.
I have learned from sad experience that there is room under the desk for a hard disk, or a child, but not both. With each of my older kids, at different times, I posed in an updated version of the Kennedy tableau: the indulgent father working at his computer while an infant frolics at his feet. And each time, just when I'd forgotten the infant was there - probably because of a burst of work-related inspiration that I had also forgotten to save - the little saboteur struck, cutting off my power supply.
Not that I blame children: it's the button that puts them up to it. So when my son Daniel turned one recently, the age at which babies and buttons start communicating, I was on guard. Sure enough, one day I overheard the PC switch whispering to him: "Go ahead, press me! See what happens!" But even if I hadn't heard, one-year-old children are as transparent as cartoon characters. When they have an idea, like Wile E. Coyote planning an ambush, it sometimes appears in a bubble above their heads. At the very least, they start hyperventilating with the excitement. So now, as soon as I hear Daniel approaching the desk with an idea, I plant a leg between him and the hard disk, and keep it there till he leaves the room.
It's not just the PC button that speaks to him. There's the washing machine as well. He hasn't managed to turn this off yet, partly because the button sticks, and partly - I think - because the washing machine provides such entertaining viewing. The pre-wash programme is his favourite. But he'll watch anything, really: even the drying cycle, if there's nothing else on.
Unfortunately there's a limit to the washing machine's entertainment potential. And yes, the other night, just in time for the World Cup, Daniel arrived at an exciting discovery that both his siblings made around the same age. Namely that, although his father appears to control the TV set from the sofa by means of a hand-held remote device, a one-year-old baby can turn the television off by pressing the button on the actual set.
It was a classic moment, straight from the child development manual. I was slumped on the sofa, watching the news, while the baby played happily on the floor. It was one of those special and increasingly rare evenings when the remote control wasn't lost. It nestled safely by my side: I was a man in charge. Then the baby had an idea. He looked at the television. He looked at me. He started hyperventilating. I knew what his idea was: I could hear the button urging him on. But I couldn't plant a leg between him and the TV - not without getting up, which was of course unthinkable.
So, pathetically, I attempted to impress upon the baby the importance of desisting from his planned course of action. I did this by speaking slowly and in capital letters: "DON'T DO IT, BABY! DO NOT TOUCH THE BUTTON!" And as on previous occasions, it was useless. A man slumped on a sofa does not have presidential authority, no matter how hard he pretends. Like his brother and sister before him, the baby knew instinctively that he had the upper hand in this situation. He pressed the button, making the news disappear. Then he sat back grinning like the bad guy in a Bond movie who has just blown up the world.
In the weeks ahead, I know this will happen a lot. I'll be on the sofa, relaxing to the sight of England losing a penalty shoot-out, or something, when a light-bulb will appear over Daniel's head. He will look at the television and then at me. The mad idea of turning the TV off will occur to him, for the first time in several minutes. He'll reach the button just as England are about to miss the decisive penalty. And my consolation will be that at least there's only one of him.
When Patrick went through this phase, his sister Roisín - then a mature two-year-old - would sometimes turn the TV back on to save her poor father getting up. Then Patrick would turn it off again, signally the start of a nightly game, in which the permutations of the on-off button were explored endlessly. It might appear to an adult that there were only two possible moves in this game. But to the kids, it was a test of strategy and cunning that could last longer than some chess matches. And even though I was never officially a competitor, it was sometimes me who conceded defeat eventually, shaking hands with both players and retiring to read a book.