Mystery Guest, Will You Enter And Sign In Please!

Yet another installation for my gallery of feeble attempts at trying to stump you lot, who are truly unstumpable! (it's a word, look it up.  well, maybe not)

IF YOU ARE NEW TO THIS GAME PLEASE READ.  If you've seen this picture before, or know for sure who this is, feel free to send me an email, but for the sake of unbridled mystery and tension, let the gang have a go at it in the comments section.

I can't imaging why the sour look on this little beauty's face, with a carriage like that I'd have been completely delighted.  But I digress.  Who is this lil punkin?