This weekend, we went to purchase a new mattress and had our four year old with us. While we were there, he was playing around; laying on the beds with us, helping customers when they came in, reading the specs on the beds, and taking pictures with one of the staff's cell phone.

Anyway, the associate who was helping us looked at ds and said, "You're how old? Five?" He told her he was four. She then said, "You're an overachiever, aren't you?" I looked up at her with what, I'm sure, was a startled look on my face. Out of the blue, she said that she has a son who read at 2.5 years old and was like ds at his age. She gave me the impression she had a gifted child and was feeling me out about it.
My first impulse was to talk about early reading, but I said nothing.

Since ds was about a year and a half, I've seen some unusual looks on people's faces, but nobody has given such specific unsolicited observations on his actions, and this is the first time someone gave me the feeling they recognized a gifted child.

I'm curious, what do you say when someone makes comments like these? Do you just smile and nod like I did, or what? Do you comment on a stranger's child that you notice has traits like your child(ren) do?

Is there some unwritten etiquette among parents of gifted that I should know?