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Mona Marshall (b. 1947) is a voice actress who voiced Mokey and Cotterpin Doozer in the animated version of Fraggle Rock. She has also been heard in Sesame Street inserts, for example voicing a little boy who gives an alien directions (First: Episode 1877). Marshall was part of the loop group for It's a Very Merry Muppet Christmas Movie, looping on-camera actors and providing background dialogue (including some Muppet crowd scenes).
Marshall's other credits include roles in such diverse series as Digimon (as Izzy), Rainbow Brite, the 1980s version of Spider-Man (as Betty Brant), and South Park (as Sheila and others).