My son’s sister is arriving soon – but why is his dad’s tummy also starting to grow?

Telling our son that he was soon going to have a little sister was one of those rare moments where we got the sort of heartwarming reaction we’d hoped. As parents, I mean, but certainly not as someone who hopes to write a palatably relatable column.

He’s continued choosing names for her – Pizza has now overtaken both Alexander and Blueberry in his top tier – and insisting, quite sweetly, that he’ll be a doting big brother once she arrives, proving it by holding toys outstretched to his mum’s stomach. It is, in short, the cutesiness of one who has learned he will curry special favour by appearing adorable. Still, we do find it adorable, so the victory is his.

I shudder to include such stories because even I find that level of wholesome cheeriness a bit much. Look, I want to relate the sweet things he does because he’s a lovely, nice boy of whom I am very fond, but if I veer too far into the saccharine stuff, I picture my cruel and cynical readership retching in their droves, blemishing this paper – or screen – with vomit in the process.

It behoves me to mask such sweetness with the thin veneer of crotchety snark that let’s me have my cake and eat it, week after week. You know, ‘Oh, I love him but he gets yoghurt everywhere and has started killing small rodents,’ that kind of thing. It’s a tactic that’s served me well for a while now and I don’t much feel like retiring it, which was making his absurdly charming reaction to news of his baby sister not just narratively inconvenient, but professionally embarrassing.

Luckily, he stepped up to the plate yesterday by offending me quite profoundly. His charming, if slightly invasive, habit of kissing his mum’s stomach and whispering hello to his baby sister led him to do the same to my pale belly, tugging at and cooing over the child inside. He has since graduated to shouting ‘Hellooooo!’ into my belly button.

We’re not quite clear if he thinks I’m also pregnant, or if we simply swap incubation duties on an ad hoc basis. Either way, he cannot be dissuaded and now speaks often of my baby, and even places a gentle hand on my stomach any time it comes within admiring distance.

I’ll try not to dwell too long on what led him to believe I, his doting father, could be with child, because this very magazine paid me money to lose a bit of weight a couple of years ago and I’m vaguely worried they’ll make me pay it all back if I confess that my build has rebounded to pregnancy-confusion levels. I will simply continue to correct him, and request he refer all such affection to his mother, in the hopes he isn’t upset to discover he has just the one sister arriving in a few months’ time. For now, I’m content to let him pat, hug and slap my wobbly paunch after every large meal. Slap, slap, slap he goes. It’s enough to make you sick.

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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