There was a Facebook post the other day that asked: What object defined your childhood? Loads of comments underneath. Tons of dafties with nothing better to do. Pictures of Space Hoppers, the towers at Ravenscraig imploding, Harry Potter, Tamagotchis, that sort of thing.

I only saw all this because my friend had replied: What about all that white dog shite, eh?

And everyone went: white dog shite, fair point. Thumbs-ups big-style.

I’m thinking, how? How did the colour of a dog's shite define your childhood? Did you read the post properly? You're saying all these calcified number twos all over the place changed the course of your life? How trivial are you?

Because I know what defined my childhood, and I can't post it on Facebook. I’ll tell you, though.

This girl in my class. She was out on her new bike, racing towards me along the pavement. Out in the rain with it and it was getting dark, so it was kind of her fault. Her legs were glistening, a doll’s shine on them. As she passed, I stretched my mouth wide with my thumbs and pushed my nose up with two fingers. She turned and shouted back, something I didn’t hear. As she said it, she swerved onto the grass verge. The bike buckled and tossed her up into an arc. Her arms swung, like she was in front of an orchestra.

There was a lamp-post in the middle of the verge and she hit it head-on. She couldn't have aimed better. I can't remember any sound. More a silence if anything. She lay on her back like she was pretending. Her hair was a weird colour. It had always been red, mind.

I'm an anxious person. I don't sleep well. I think of her even more now, just before dawn in particular. My spine prickles and I wonder to what extent my fingers and my nose were to blame for what happened that day. What did she say to me? It eats at me, if I'm honest. So you can understand why I get angry at frivolous Facebook threads.

Until I think: what if that girl skidded on one of those wee white shites? I mean, it's unlikely. But she could have. Those verges were riddled with them.

I hope she did, anyway.

That way everything would make a lot more sense.