Who is Abigail from Dragonwyck and what is their importance?

Abigail is more than Miranda's mother.... she is her best friend. She is proud of her daughter, as well as her daughter's aspirations and dedication to bettering herself. Although Abigail is never invited to her daughter's home and is unaware of everything that happens there.... she surmises everything isn't as it should be. She is, however, overjoyed when Abigail and Jeff marry in the novel's conclusion.