One just a nit picky note: are they supposed to be kids? I guess the girl in the blue shirt could have gone through puberty already, but then she feels kind of out of place with the whole scene. So, if she's not actually in her mid teens - why does she boobs?
Otherwise, I love the expressions and the roundness of the characters.
I love the design! But I didn't understand that those were shoes until I saw the note on Flickr. On a t-shirt it would probably be even harder to see, unless you're like, staring really closely at the wearer's chest. :P
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