Fourteen chapters (!) mention Old Nan’s stories, most of them more than once. I was originally going to do a story accuracy scoreboard, but the idea seems to overwhelming now. I was amazed at the degree to which all the Winterfell-based characters* incessantly return to the phrase “Old Nan’s stories” to signify both the respected wisdom of the past, and the supposed silliness of things everyone supposedly knows aren’t true. That’s one conflicted relationship with history, legend, and magic there.
*Even Catelyn, who was exposed to Old Nan only after she was old enough to know better! If anything, she should be remembering “Old Mabel of Riverrun”‘s stories or the like.