The Simpsons S31 E21 The Hateful Eight-Year-Olds

"Just a product of society that's lost its good manners."

After severing her sibling ties with Bart, Lisa attends a sleepover at her new friend Addy's house, only to discover that Addy's clique are a group of cruel snobby rich girls that taunt her. Meanwhile, Homer takes Marge on a sunset cruise for the evening and finds himself at odds with the boat's cover band.