Our four-year-old is running rings around me

My son turns four in a few days, and it feels big. Four years is a lot: the tenure of American presidents, the gap between World Cups and, to a lesser degree, European championships. Four years is the first age at which I have definite, clear memories of my own life. My first day in reception class, the smell of cheese sandwiches and hugging my teacher’s shaking legs as my mum left the room. There’s a vertiginous sense that the record button in his brain has well and truly switched on, and I should make a better effort not to say the wrong things.

He starts school in September so maybe it’s best he doesn’t go there thinking I’m actually the world’s strongest man, that I used to work with three of the pups off Paw Patrol, or that giraffes look so weird because they’re originally from Mars, but travelled all the way to Earth in search of their favourite food, burgers and chips.

Luckily, he’s working these things out for himself. The highlight of my day, every day, is his bedtime. This was once the time I read him stories and then had a short, sleepy chat before saying goodnight. Most nights we now just talk. It’s an odd kind of chat, admittedly, since many of his tics are skimmed from conversational cues he’s lifted from the adults around him. ‘Daddy,’ he’ll ask, with an urgency hard for a four-year-old to justify while hugging his father in bed, ‘what counties do you go through to get from Dublin to Derry?’ I haven’t begun to answer before he lists them off, fresh in his memory from the Counties of Ireland jigsaw he does several times a day and can now finish in around a minute. I’ve yet to do it in under three. ‘That’s if you’re driving,’ he assures me, with the corrective tone of a middle-aged civil servant, before listing the alternative counties bisected on the equivalent journey by train.

He peppers me with other questions and corrections, mostly concerning space and dinosaurs and the impossibility of giraffes on Mars who eat burgers and chips. I tell him maybe I’ve got it wrong and they live on Jupiter. He tells me you can’t live on Jupiter because it’s made of gas. A bead of sweat forms on my temple.

Every night he corrects me a little more than the last, and when he tires of it, he ends with the same question: ‘What was your favourite part of the day?’ This used to be my closing line, but recently he’s started beating me to the punch. My answer always involves something we’ve done together: a walk in the park, making Play-Doh figures or doing farting noises with our mouths and blaming the resulting noises on his nana. These are all great options, but the real answer is right there and then: chewing the cud with him in a strange facsimile of adult conversation, forced to raise my game as an astounding, marvellous, terrifyingly near-four-year-old boy sleepily runs rings around his father.

Did Ye Hear Mammy Died? by Séamas O’Reilly is out now (Little, Brown, £16.99). Buy a copy from guardianbookshop at £14.78

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