Lisa Simpson is the second oldest child in the Simpson family and one of the rare people in the show that uses any common sense. Even though Lisa is proud of her 156 IQ she is still shown to be very self conscious in some areas and is picked on at times for being so intelligent. Because Lisa is so intelligent she was allowed into the Springfield chapter of Mensa. The other members include Principal Seymour Skinner, Dr. Julius Hibbert, Lindsay Naegle, Jeff Albertson A.K.A Comic Book Guy, and Professor John Frink. Lisa loves the Itchy And Scratchy Show, Malibu Stacy dolls, and ponies.
Bart is Lisa's ten year old brother and the two are mostly seen either fighting or arguing. At very rare times Bart and Lisa have shown that they care about each other and have worked together a couple of times as well.