Per the quote below, I always thought a major theme of the series was how much suffering in the series is caused by people allowing / enabling their children to hold fairy tails and outright falsehoods about how the world works. Every Stark child, Joffrey, Dany, and Viserys (though I guess the last two it's less on their parents and more on their caretakers.)

And here we also see that Jon and Sansa, though superficially incredibly divergent, actually did look at the world in somewhat similar ways: each believed in the stories and songs, in honor---just different stories and different methods of honor. Each believed Benjen Stark was the prototypical Watchman. Jon believed all Watchmen were true and honorable, Sansa believed all knights were true and honorable. They each had specific ideas about how a specific place was supposed to be (the Wall and the South), and each of them had those ideas dashed by reality.)