Final answer:
The question asks about a specific 'amazing secret' that a character named Lily stumbled upon, which is likely a significant plot point or character development in the text. The exact nature of Lily's discovery depends on the context of the literary work, which is not provided. Literary secrets typically have profound effects on the characters and narratives involved.
Step-by-step explanation:
The "amazing secret" Lily stumbled upon varies depending on the context of the literary piece being referred to. In the provided texts, there are several instances where characters discover or keep secrets, but it is not entirely clear which Lily and secret the question pertains to without more context.
Secrets in literature often relate to character backstories, plot-driving revelations, or personal transformations that significantly impact the narrative.
For example, in one narrative, Lily Dyer discovers a personal truth that she feels no qualm about walking past Louisa Ellis, who had possibly sold her birthright without understanding the gravity of that choice.
On the other hand, in another story, the secret might refer to Bess's true identity and her connection to Milly, the locket, and how these revelations transform her perception and the perceptions of those around her.
The nature of Lily's secret in these contexts is deeply personal and has wide-reaching implications for her character development and the story's outcome.