Sofie is a humanoid Muppet girl on Big Bag. A cheerful six-year-old, with purple skin, fuchsia pigtails, and glasses, Sofie moves next door to Molly's shop in the show's second season, and befriends Chelli and Bag.

Sofie got her name from a contest that CTW held in 1997, in which kids voted for one of five available names for the character.