Leo loves Where the Wild Things Are (and I love Maurice Sendak). We've never seen the movie but Leo has been practicing his "I'll eat you up!" and "Be still!" for weeks.
If you have never read more by him, I highly recommend the Nutshell Library (Pierre!) and Outside Over There.
I used the pattern by Jessica from Running with Scissors, available here. I made size 2, and enlarged the head for Leo's noggin, but it is a bit too short in the trunk. The pattern was easy and thorough (with links to videos for the tricky parts) and includes fox and bear (Ewok) variations.