Ten Life Lessons The Simpsons Taught Us Over the Years
The Simpsons has demonstrated this several times in the past 25 Years, for example, when Homer was accused for sexually harassing a woman, Marge and the Kids stood by his side, when Bart was getting death threats by Sideshow Bob, they stood by his side
Watch Lisa on Ice and you'll see the flashbacks of Bart and Lisa lending each other a helping hand. If you remember this bit, that's what I'm talking about.
"I cannot bail on a friend, even if it is Ralph" Said by Bart Simpson in 'This Little Wiggy' when he faces a dilemma whether he should ditch Ralph and go into the prison with the bullies, or stick with Ralph. This shows how friends should always have your backs and vice versa,
This is a good example too. Lisa's views are very different from other Springfieldians in various episodes, and her family, but she is accepted too, also when Homer was against John because he was gay and he was afraid that Bart was gay too, John saved Homer and Homer accepted John as a friend.
This is also a good example, Homer goes to work not because he has to, he does it for Maggie.
Even if you hate your brother/sister so much, they are very important to you. Bart and Lisa, they don't like each other very much, they always look out for each other, for example, Bart got Michael Jackson, or Leon, to sing for her on her birthday, Bart bought the Bleeding Gums Murphy Album after his death for Lisa because she was the only one who believed him when he swallowed a jagged metal in his krusty cereal.
All of the characters that drink end up really dumb.