I don’t think his mum noticed me at that point, she was too busy attending to her child. And this is what she did. She went down on one knee, hauled the little lad to his feet, then very efficiently and quickly took down first his trousers (which conveniently had an elasticated waist) and then his underpants, which I noticed had an aeroplanes pattern on them.
Mum then proceeded to put her now bare-bottomed boy over her raised knee and began to smack his bum very efficiently and quite hard, producing more screams but eventually melting him into tears of submission. That little bottom was soon covered in red handprints.