Here's a very different sort of character evolution.
We professional cartoonists like to create work that amuses both ourselves and our peers, and occasionally forget that we are actually creating product for a children's network. Luckily, there's a whole bunch of people whose jobs are to make sure no one oversteps the boundary.
I thought it was pretty funny to see Bernie Peterson's sexy Coppertone girl (for upcoming ep "infectious Personality") have her innocence restored in this series of revisions and re-revisions. Katie Rice and Jill Friemark did the designs.