Three little boys were riding in the back of a family car. The windows were open, warm air was whipping around them, and the boys were shouting with pleasure at the genius of their own wit.

Readers with delicate sensibilities may want to stop here, because the boys in question ranged from 5 to 7 years in age, and everyone knows what they think is humorous.

"Poopy diaper!" yelled one of the boys, with wild originality.

"Poopy diaper head!" yelled another.

"Poopy poopster diaper head pooper!" yelled the third.

"Poo -- look!" shrieked the first. All three boys screeched. They rocked back and forth, falling over each other. It was unbelievable. There, right beside their car, was a flatbed truck carrying portable lavatories. It was traveling at their speed. They were right next to it! Could anything be funnier?

"Don's Johns," read the most literate of the three, for this was the name of the company to which these porta-potties belonged. He started to sing: "Don's Johns, Don's Johns, Don's poopy Johns."

"Poopy poopy Don's Johns," the second boy chimed in.

"Don John is poopy!" cried the first. "Poopy Don John -- "

"Hey," said the third child, who was no longer laughing. "Stop making fun of me."

There was a moment of mystified quiet, which was broken by the driver. In her early days of driving children around, she had enforced a ban on low bathroom humor and would never have let small boys shriek in such a way. But the years had mellowed her -- or broken her -- and now when she transported her youngest child and his friends, she no longer interfered unless someone was getting hurt.

This was the case now, though inadvertently. The third boy was often slightly out of kilter with his peers. Though his peers scarcely seemed to notice, adults did -- in a way that caused them to nod both knowingly and sympathetically. For instance, when other boys turned sticks into swords or lightsabers, he'd be using his as a magic wand. In games of freeze tag, he'd come to a halt with an arm and leg delicately outstretched, like a ballet dancer. And his name was Johnny, a name close to John, which, of course, was the word the boys had been rudely yelling.

"Oh, no, no, no!" said the driver reassuringly, making eye contact with Johnny in the rearview mirror. "No one is calling you names. Everyone was laughing at the porta-potties, not at you or your name. I think," she went on, "that it's mostly just an excuse to keep saying the word 'poopy.' "

"Yeah," said her son, "Poopy poopy. Call me Mr. Poopy!"

"Call me Mr. Poopy!" cried the second boy.

"Call me Mr. Poopy diaper head!" returned the first boy.

"Call me Mr. Poopy head Don John diaper poopy head!" shrieked the second boy.

"Call me ... Helena!" yelled Johnny.

There was another moment of silent confusion. The driver thought: One of these boys is really not like the others. She was about to intervene to protect Johnny's feelings, when, to her great relief, the two boys caught their friend's odd contribution and ran with it.

"OK, Helena poopy face!"

"Helena poopy face diaper head!"

And as the car zoomed along the road, the boys were off again, caterwauling and squealing and killing themselves with laughter.

Meghan Cox Gurdon's column appears on Sunday and Thursday. She can be contacted at