Charlotte's statement about the migrating geese, "Somewhere in distant lands they are still flying. It is only because our eyesight is too weak that we can't see them. It's the same with people who die", acts as foreshadowing to the news of her own death in the final chapters of the novel. Even though she has died, she continues "flying" through the book the narrator is writing about her life, memories, and stories.
Dreams of My Russian Summers, pg. 122