Sam, aged 3, had been catching invisible baby dragons all morning long. Cupping his hands together he carefully showed me  all the blue dragons, red dragons, yellow dragons he’d captured around the house. They were all  very cute – if a little invisible.

Later that afternoon he appeared at my side with his proffered hands cupped,  just as before. I don’t know what possessed me but I grinned and clapped his hands together. I will never forget the expression of horror on his face.

Now smeared across his palms were the remains of a spider.