"Oh, look, that dog has such pretty eyes," she said. "One's blue and one's brown."
"Is it a girl dog?" the little boy asked.
"I think so," she said. "Yes, she's a girl," she said, more firmly.
"How can you tell?" asked her son.
"Well, she doesn't have a penis."
"What doesn't she have?"
I could sense Mom's unease with this conversation in a public place.
"She doesn't have -- have a -- boy part," she said.
"You mean a PENIS?"
"Yes. She doesn't have a penis."
"YOU don't have a penis."
And what am I doing while this fascinating exchange is going on? Oh, I'm staring off into space, doing my best impression of someone who is either deaf or distracted. But behind my poker face, my Sense of Mischief is doing a wild jig and blowing raspberries at the Moon, lemme tell ya.
Small children like facts. Learning facts makes them feel secure in the handle they're getting on this world they're in the process of inheriting. Knowing (and demonstrating) facts makes them feel confident in their increasing mastery. And whenever there's a possibility that they might be getting into new territory, they always want to confirm the facts they already know. Basic facts are largely matters of vocabulary, which they like to exercise.
So, good for you, Son. I'm glad to see you're getting the world sorted out properly. And good for you, Mom, for teaching him important things, with the right words. Don't worry about it; we've all been there.