It takes a while to get the character to look like you see it in your mind. At least for me it is. Some artists can just whip up a drawing in a matter of minutes...I tend to doodle for hours. Here are some other versions of the characters. 

Charles the Third!

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The grasshopper went through a lot of different versions.
The bug!
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Not sure where I was going with the one on the right
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Apparently I was going for alien at first...
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With boots!
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Almost used this one.
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Another alien?...

Gabriel!

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The first time I started the book, I drew Gabriel older. Eventually, I made him younger and cuter. Cuter is always better.
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I had someone else color this. They did it, of course, using Photoshop. Then I thought, I'm a traditional artist...what am I doing?! Luckily, he stopped responding to my e-mails so I gave up on this version. :)
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I kept having to redraw this one until I made him into a little kid. That's Gabe modeling! This picture still is not quite right in the book but I just like the way it came out so I left it.
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When I first started, I drew Gabe as a very simple drawing. It was meant to be a sample of what the story would be like. This is before I finally decided to illustrate it myself.
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Too realistic and too old.
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The final one.
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The older more realistic version again and more versions of the grasshopper.