When I was a kid, maybe 9, my brother and I drove down to Mexico with my grandfather and my six-year-old uncle Juan.

Looking back on it, making that four-day drive in a station wagon alone with a 9-year-old, a 7-year-old, and a 6-year-old must have required my grandfather to draw mightily on the reserves of strength and discipline he acquired in the United States Marine Corps.

We rode in a blue Ford station wagon—a serviceable automobile. Nothing fancy. Vinyl seats (which we stuck to), lap and shoulder belts (which we assiduously ignored), and an AM/FM radio (which my grandfather never turned on because he liked the silence. Four days is a lot of silence for a nine-year-old I don’t mind telling you.).

That old station wagon ran well. My grandfather, the urban commando, used the radiator to cook hot dogs for us instead of needlessly stopping at restaurants.

But most importantly, that station wagon had an air conditioner—which, if you’re driving through Texas in the summer, is no small thing. The air conditioner leaked, however. So, we put the dump truck part of a Tonka truck under the dash to catch the distilled water that dripped out—so it didn’t soak the plush station wagon carpeting. Every time we stopped—which amounted to about twice a day—we were supposed to empty the dump truck on the ground outside.

When we got down to Brownsville, we had to prepare for a full day’s drive through the Mexican mountains on our way to San Luis Potosi in central Mexico.

Hard driving. In the mid-70s, you could drive all day and see fewer than ten cars. And guess what? Not a single McDonalds, no Dairy Mart convenience store/gas station. Just cactus. And dirt. Cactus and dirt all over the place. But no rest areas.

We crossed the border into Matamoros on this particular trip, and it was like 105 degrees out. Somebody said—I don’t remember who—“I’m thirsty.”

After three long days in the car and countless radiator hot dogs, that was the wrong thing to say in front of my grandfather.

“Didn’t I tell you to get something to drink back in Brownsville? Didn’t you bring the water like I told you?”

“Um, I thought he was getting it,” we all three pointed at each other.

“Well, there’s nothing out here. We’re not going to have anything for a long time.”

Now, regardless of who brought up the thirsty thing in the first place, hearing that we were driving through the suburbs of hell without any realistic hope of getting a drink made all of us thirsty. Really thirsty.

So, we started whining. Whining was something that neither the Marines nor raising fifty kids in a children’s home had prepared my grandfather to handle gracefully. He didn’t have much use for whining—and by “not much use,” I mean “no use.”

“I told you. You didn’t listen. Now, you’re just going to have to wait.”

There were sniffles, I seem to recall. Not out and out crying, which would have further exhausted the supply of liquids we were hauling around in our little bodies.

Tough as he was, I think our solemn dejection finally got to my grandfather because he said, “All right, look. If you can’t wait, then drink the air conditioner water out of the dump truck.”

Now, even to us—the mini-adventurers who’d consumed so many Oscar Mayer wieners fresh off a hot engine block—this sounded sketchy. I was pretty sure my parents wouldn’t want me drinking air-conditioner water out of a plastic dump trunk.

But we were so thirsty.

I took the bed of the Tonka dump truck filled with distilled air conditioner water and passed it over the front seat to my younger brother and my even younger uncle Juan. I suspect that I thought letting the younger ones go first demonstrated my maturity. And in retrospect, I suppose it did.