| Chet Simpson|
|Occupation||Runs an unsuccessful shrimp company|
|Relatives|| Father: Orville Simpson|
|First Appearance||"Lisa the Simpson"|
|Voiced By||Dan Castellaneta|
Chester Oliver Simpson (or Great Uncle Chet) is Lisa's great uncle who runs an unsuccessful shrimp company. He could be either Mona or Abe's brother, but most likely the latter's. Judging from his looks he is the youngest of Abe's brothers.