"Why is that funny?"

I was sitting on the playground, which is expressly forbidden, surrounded by a group of children I had been telling a story. I often tell stories at work—things I make up about Darth Vader attacking the playground, jokes about children disrespecting authority, Greek myths, O Henry short stories—it’s convenient when you need to fill five or ten minutes of time while you wait for lunch to be ready, or keep a group quiet while they wait to get off the van and go into school.
I had just finished a story about Mister and Missus Carrot. They meet, go on some dates, fall in love and get married, then Missus Carrot gets run over by a truck. Mister Carrot is frantic, sitting in the waiting room at the hospital and tearing his green carrot hair while the surgeons try to save his wife. After a number of hours in surgery the doctor emerges and tells him that Missus Carrot will live, but will be a vegetable for the rest of her life.
This is an old joke my mother used to tell me, and the kids never get it. They don’t know the other meaning of “vegetable,” and invariably ask after the joke is over, “Why is that funny?” I assume the story is a failure, but then, for reasons I can’t explain, a week later they will specifically request the carrot story by name. Kids are a mystery.
After this particular telling however, before anybody could ask, “Why is that funny?” a very bright girl (the one who told me about the Pirate intestines) asked a different question.
“What is flirting, Mr. Everton?”
I had to think for a moment about where the question came from. I had described Mister and Missus Carrot “flirting” before they started dating, and hearing a word she didn’t quite grasp this girl had held onto it patiently through the rest of the story so that she could ask its meaning. The answer was a struggle:
“Flirting is… when a boy or a girl likes someone, and they want to show the person they like them, so they smile at them and joke with them and try to feel the situation out to see if the person likes them back, but subtly.”
“What’s ‘subtly?’”
“It means they do it carefully, instead of just walking up and saying ‘I like you.’”
“Why don’t they just say ‘I like you?’”
“It’s hard to explain. It’s just what people do.”

The next day I picked this girl up from school. I chatted with another van driver as I waited for the bell to ring, and when the kids came out this little girl hurried up to me with a look of satisfaction on her face.
“I was on the playground and could see you in the bus loop. You were flirting.”
“What? With who?”
“The lady parked behind you.”
“No, I wasn’t.”
“Yes, you were. You were laughing and smiling at her, and now you’re trying to be subtle about it.”
“I see why you say that,” I said, “but I really wasn’t flirting. For one thing, that teacher is engaged. We were just having a friendly conversation to kill time while we waited.”
The girl looked at me, unsure of whether I was honest.
“So how do you know if someone is flirting or just making friendly conversation? Isn’t it kind of the same thing?” She looked at me with genuine curiosity.
“It’s complicated,” I said feebly.
“You don’t really know very much about it, do you Mr. Everton?”
She’s quite a sharp little girl.