To explain recursion to a six-year-old, first explain it to a five-year-old, and then wait a year.
Actually, this is a useful counter-example, because your recursive call should be simpler, not harder. It would be even harder to explain recursion to a five-year old, and though you could stop the recursion at 0, you have no simple solution for explaining recursion to a zero-year-old.
To solve a problem using recursion, first sub-divide it into one or more simpler problems that you can solve in the same way, and then when the problem is simple enough to solve without further recursion, you can return back up to higher levels.
In fact, that was a recursive definition of how to solve a problem with recursion.
