Who is Daisy Wapshott from Possession: A Romance and what is their importance?

Daisy Wapshot is the wife of the deceased Mr. Rodney Wapshott, who was the son of Ash's godchild, Sophie. Daisy lets Cropper see letters that her husband inherited when his mother died. She is a bosomy lady and very hospitable. She is considering selling the letters to Cropper for his collection.