I can't remember exactly why we were talking about this, but if you happened to be a passenger in our van this weekend, you might have overhead this:
"Madeline, how do you know that Fancy Nancy doesn't live in Vietnam?"
My six year-old's reply, "Because the street she lives on does not have all of this garbage on the road!!!"
Well, yes. That would be a clue. Not the one that I might have used, but looking out the window at the roadside, I have to admit that she is correct nonetheless.