The Dark by Lemony Snicket, illustrated by Jon Klassen. Ive looked at this as Jon Klassen is a favourite children's book illustrator of mine, his work is child friendly but quite sophisticated in the overall look of the work he creates. In reference to the theme of my book being Pandoras Box, this book uses dark and light and the idea of fear in a child friendly way.
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I feel like this type of illustration could work in The Saturday Paper. It will be read by creative young professionals around 35-49. So I think this type of illustration won't be too childish as long as I use the proper colour scheme.