If you have an occasion to have or read kids books, you might have read the famous I Want My Hat Back by Jon Klassen. Or the great followups This Is Not My Hat and We Found a Hat. Really everything he does is good. My favorite is Triangle and there is a pretty laugh-out-loud-y twist in his version of Billy Goats Gruff.
But the new best is The Skull.
Everything he does is a little dark, but this is extra dark (but not in a way that a kid can’t handle it).
This little girl runs away from home, escaping an unknown bad situation, and come across this big house int he woods where this skull lives. It literally hops around and talks. Turns out the skull is also in a bad living situation, and this little girl has had it. The steps she takes to help the skull get out of this situation, and thus help both of them, are uh, pretty hardcore.
I love these books. I remember reading I Want My Hat Back all the way through, while standing in a bookstore years ago.