Of course, it happened in the grocery store. Is there any other place?

Many years ago my wife and I were with our son Alan, who was a toddler, picking up some groceries for the week. All our items had been scratched off the list, so we made our way to the Bermuda Triangle of parenting, the checkout aisle. We reached the front of the store, picked the shortest line, and parked our cart there. Candy glittered on the shelves.

Perched in his seat at the rear of the cart, my son leaned over the edge, stretching himself toward the stacks of sweets. His eyes were bulging.

“I want candy!” he exclaimed, reaching for it.

He hadn’t yet had his dinner. Besides, he was too little to eat a whole candy bar. Being the wise new parents that we were, my wife and I gently denied his request. “Not today, honey,” we said.

If only it could’ve been that easy.

In a matter of seconds, our sweet little child transformed that checkout aisle into a nightmare. He arched his back, strained his face, clenched his fists, pounded on the cart, and screamed. “I want candy! I want candy! I! WANT! CANDY!”

As the entire store turned to look, my wife and I made eye contact. In that moment, I had a single thought. We’re raising Hitler.

It’s moments like those that truly test a parent’s self-control. As the child spasms and spits in the checkout lane, we’re forced to ask two key questions. First, when my child is throwing a fit for the whole world to see, how will I respond? And secondly, when I feel like I’ve lost control in my parenting, how will I gain it back?

Really, it’s the second question that’s the more important one, but it’s the second question that often gets neglected.

I used to work with teenagers all day, every day, and their parents would often come to me at wit’s end. They’d tell me they’d lost control completely—that their kids didn’t obey them, wouldn’t listen to them, refused to respect them. How, they’d ask, can we change things?

The sad truth was, when they’d finally recognized the problem, those parents had already reached a point where adjustments would be difficult. By the time the kids hit middle school, they’d been programmed, more or less. They’d established patterns of disobedience. They’d gotten used to their disrespect being tolerated. They’d been let off the hook enough to count on it happening again and again.

Here’s the thing: teenage disrespect and disobedience rarely pops up out of nowhere. It’s almost always rooted in something. All too often, it’s rooted in something as simple as a supermarket tantrum.

I’m not going to pretend that this kind of thing is easy. Frankly, it’s embarrassing to have your control-less moments on display for the world to see. It’s tempting for parents to choose a quick fix—to holler right back, to ignore the kid completely, or to pacify them with a King Size bag of M&M’s.

There’s a problem with the quick fix, though. Although it stops the screaming for a while, it does absolutely nothing about the next time. And in parenting, next time is definitely something to be concerned about. Next time, they’ll be teenagers.

If we want our kids to learn obedience, we must make a habit of upholding parameters. If we want them to be respectful, we must offer discipline that’s consistent. If we want them to listen, we must speak in a way that invites hearing.

And we must begin in the beginning. Yes, that might mean we’ll have to begin in the grocery store.

So if that’s your kid pounding the floor in aisle five, go ahead. Take advantage of the opportunity to do some parenting, right there on the spot. Sure, you’d rather flee the scene, but next time you’ll be glad you didn’t.