He is approximately of Hilda's age. He has a slightly tanned skin, freckles, and brown, curly hair.
Not much of him is seen in the series, but at first glance he seems to be a trouble maker, or at least a bit on the clumsy side.
In "Chapter 12: The Nisse" when, during the Sparrow Scout camp, Raven Leader send the scouts on a scavenger hunt, she specifically addressed him to remind him to stay with his group at all times. Willy himself was hiding in the bushes behind her and suddenly popped up after she called him. She had to remind him again when the groups left the camp because he accidently went the wrong way.
- So far, he is the only Sparrow Scout besides Hilda, David, and Frida whose name has been mentioned on screen.
- He only appears in the animated series.
- He's apparently the clumsy one of his group.