I need a character design for my kids magazine

Information for the business: A children educational magazine
Industry: Publishing/Journalism
Design details: I am in need of a Buffalo design for my kids magazine. The magazine is a children magazine for learning English through creativity.
I have some initial sketches that I would like to be made up, but they would need some work.
Ideally I would like the buffalo to be in various positions like running, sitting, eating, reading, writing and this is something we need to talk about. I would like full use of the copyright and be able to change the designs if needs be. So I would like the illustrator files too.
Target audience: Childrens. 6-12 years old.
Messages to communicate through the design: A children character that is friendly, funny and a icon to getting children to work.
I don't want him looking sad or dopy but enthusiastic.
I want to create a character that will go off on adventures and enjoy the world around. He will be inquisitive.
Ideas for the visual style: Happy, fun, cute.
Things to avoid: I don't want him looking sad or dopy.
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