Not talking about the defective, naughty "Pre-Gremlins" that you get when water hits them,... but actual natural reproduction.
Does it occur only, like, every 100 years?
Are there any female MogwaisMogwai in existence? (Keep in mind, Gimzo is explicitly referred to as a "he", and we saw a distinctly female Gremlin in the second film.)
Or, much like the rules governing their general care, are there some specific circumstances that have to allow for a Mogwai to reproduce naturally?
I mean, they couldn't just pop into existence, could they?