There's only one test of a great children's book, or a great children's film, and that is this: If it can be read or viewed with pleasure by adults, then it has the chance to be a great children's film, or a great children's book.
The whole essence of good drawing - and of good thinking, perhaps - is to work a subject down to the simplest form possible and still have it believable for what it is meant to be.
The author O. Henry taught me about the value of the unexpected. He once wrote about the noise of flowers and the smell of birds - the birds were chickens and the flowers dried sunflowers rattling against a wall.