It had started as a way to block out the shouting and the general unpleasantness of it all. He would sneak out of the backdoor and press his face in between the posts of the fence, staring at the cars as they drove past him along the road.
If he spotted at least one yellow car, then maybe Dad wouldn't hit Mum today.
If he happened to see two of them, perhaps his parents would stop fighting for a while.
And if he was lucky enough to see three in a row – who knew, they might even never argue again.