'Always keeping an eye on your kids to see any sign of one turning into an axe-murderer'

My five-year-old bumped into his best friend on the way into school yesterday morning. They did this thing of jumping up and down, excited but cautious too, just in case the other one had decided to be best friends with someone else overnight. (Being five is tricky.)

This jump-dance ritual seemed to re-cement the friendship so they started punching themselves on the forehead and talking to each other in a high-pitched, nasal voice. There was something familiar about the way they did it. And then it came to me – they’re Beavis and Butt-Head.