Betsy

 Betsy  is Oscar the Grouch 's Grouch dog. Oscar enters her as an entrant in the Yucchiest Pet contest in the 1994 book  Oscar 's Grouch Jamboree. Betsy & Slimey  both end up losing to  Grundgetta 's  muddy  piglet.

Books

 *  Oscar 's Grouch Jamboree (1994)