Deaf-related gift for 4 year old


i tutor and mentor a young, enthusiastic hearing mother of a toddler who is turning four in two weeks. I would like to buy this girl something Deaf/ASL related, but I'm not sure what.... Any suggestions?!

A bit about her: She is a SUPER happy girl who loves looking at the pictures in books, animals, and the Signing Time TV show.. But she especially loves Mickey Mouse!