Mumy provided the voice of Mertle Edmonds (Lilo Pelekai's rival) in Stitch! The Movie, Lilo & Stitch: The Series, Lilo & Stitch 2: Stitch Has a Glitch, and Leroy & Stitch, and voicing a character with a smaller role on American Dragon: Jake Long as Haley's rival at school. She is also the voice of Twinkle on Higglytown Heroes and the voice of Human Kimberly on Nickelodeon's Catscratch. Lesser roles included TV appearances playing Rachael/Rachel in six episodes on My Wife and Kids from 2002-2004 as well as young Donna on That '70s Show and guest starring in Scrubs as a girl at her birthday party (whose face J. D. daydreams of shoving into her cake). She also voiced Panini in the cartoon Chowder, airing on Cartoon Network and played Lula in The Cleaner in 2008. She also voiced a feisty, fashionable, pink-loving, golden retriever puppy named Rosebud in the Disney movies Snow Buddies, Space Buddies, and Santa Buddies. In June 2012, Mumy started voice work as 'Beth' in Bravest Warriors, an animated series created by Pendleton Ward, produced by Frederator Studios for their channel, Cartoon Hangover, a premium content partner of YouTube. Mumy also provided the voice of Roxy in the Nickelodeon dub of Winx Club. She is also the voice of Leni Loud on the Nickelodeon show, The Loud House.