I don't know if you're familiar with Ernest H. Shepard, but he illustrated the wonderful Winnie-the-Pooh books for A.A. Milne. I love the illustrations he created. They are soft, simple and just lovely.
Ernest Howard Shepard (December 10, 1879 – March 24, 1976) was an English artist and book illustrator. He was known especially for his human-like animals in illustrations for The Wind in the Willows by Kenneth Grahame and Winnie-the-Pooh by A. A. Milne.