Snoopy

Snoopy is Charlie Brown's beagle who acts anthropomorphic, except he almost never wears anything except a collar, and he almost never speaks or sings (the exception of the latter two being "You're a Good Man, Charlie Brown" and "Snoopy!!! The Musical", but in neither one's animated version does his mouth move to his dialogue because none of the human members hear him talk; however, the children do seem to hear him in the number "Just One Person" as Snoopy counts himself as the first, and then he is joined).