I was an only child in a middle class family. My parents weren’t particularly strict, but believed in a firm set of principles of behaviour. I didn’t have any trouble with this, being generally in agreement and, I think, reasonably well behaved.
But if I did transgress, and do something contrary to their wishes (and usually something about which I was ashamed), I would naturally and inevitably expect to be punished. My mother always took responsibility for my punishments.