Cars parked on the side of the interstate

This morning on the way to drop the big boys off at daycare, Nate noticed that there was a car parked on the side of the interstate.

"Mom, why is that car there?" Nate asked.

Not really knowing, I came up with the best possible answer I could think of, "They probably ran out of gas."

Then when we exited the interstate there was an 18-Wheeler was parked on the side of the exit ramp.

"Did they run out of gas?" Nate asked.

Yes, I could have just said "Yes", but I like to try to give as truthful of answers as I can.

"No, they are probably just sleeping." I said.

Nate concerned said "You can't sleep and drive!".

I said "No, honey, they have beds in their trucks and they pull over to sleep".

Then I made a mistake...I got in over my head with a cartoon analogy.

"You know, like Optimus Prime, he has a bed in him." I said.

Nate quickly corrected me that this analogy makes absolutely no sense.

Nate said "Mom, there is no man in Prime. He just drives his-self."

I conceded.