Groundskeeper Willie: Brothers and sisters are natural enemies. Like Englishmen and Scots. Or Welshmen and Scots. Or Japanese and Scots. Or Scots and other Scots. Damn Scots, they ruined Scotland!
Skinner: You Scots sure are a contentious people.
Groundskeeper Willie: You just made an enemy for life.
[Bart and Lisa are fighting over the television remote and land on an episode of "King of the Hill"].
Hank Hill: Bobby, I got propane in my urethra.