An immature rabbit is not a bunny, it's a kit.

Maybe to breeders. Most people I know say "baby bunny".

So what you are saying is that "lamby" is just as attributable to adult members of the pie spieces?

If you're going to generalize from one example, then why is it that Joyce references a "moo-cow," but never mentions a "quack-duck" or a "trumpet-elephant"?

That's an interesting question. I have seen "cluck-hen", but not often. And there is a website called "Meow Cat".