From Wikipedia, the free encyclopedia. Melissa Altro (born May 16, 1982) is a Canadian actress best known for her voice acting. She has lent her voice to such animated roles as Pippi Longstocking in the 1998 series Pippi Longstocking, and Muffy Crosswire in the long-running PBS animated series, Arthur. Altro guest-starred as Alex in a 1994 episode of Are You Afraid of the Dark? and on Grossology... show more