Lucy first appeared during the episode, "Big Fat Alien Wedding". She is Camille's cousin, and comes to her wedding to perform as the flower girl (much to Gwen's disappointment, since she was going to be the stand-in flower girl when it seemed Lucy wouldn't be able to make it). Like Camille and Camille's parents, she is also a Sludgepuppy, but this wasn't shown until almost at the end of the episode, when Ben trips on Lucy's "feet" when they are dancing at the wedding reception. She is at this moment, Ben and Gwen's second (or third) cousin.