I've recently done some funny character sketches of what my little dog and cat would appear like if they were my human daughters. Yes, maybe I'm weird. :) It's a fun excercise though.
Here's an old sketch of my animals as animals:
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and now as people (they've switched places, my dog is now the little annoying sister)
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This was a really quick idea, but I like Natasha's beat-up doll as a prop, and Snooper's icecream cone. (She's a little chunky.)
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My in-laws have three dogs and two cats, and my parents have two cats... this was really fun so I think I'll try it with them too.