Ernest the Grouch is Oscar the Grouch's brother. He looks like Oscar, but with big black eyebrows, a scuzzy green mustache, and a white collar and blue bow tie.
When Ernest came to visit his brother on Sesame Street, Oscar decided to prepare an unpleasant surprise for him by decorating his trash can, dressing in a tux, and treating Ernest like a gentleman. Determined not to let him have the last laugh, Ernest returned the favor. Soon the two of them were trying to outdo each other, each asking Gina to fix the other a special treat at Hooper's. Finally, their grouchiness was returned when they found themselves fighting over a concoction only Grouches would enjoy.