Mashy the Pup, the roadkill who tells the Tree Weasels' backstory, is based on the Bagdasarians' pet Pekinese dog Tiger Lily, who was hit and killed by a car during the production of
The Chipmunk Adventure (1987). This joke was added by
Bob Jaques as an act of revenge aimed at Bagdasarian Productions for not crediting him for his layout work on that film.