Who is Mrs. Drummond from Rebellion and what is their importance?

Mrs. Drummond is the MacGregor's cook. She is described as sturdily built with the hands of a man. She can also make a delicate pastries and is highly capable. Over the course of the novel, we learn that Mrs. Drummond has set her sights on the reserved valet, Parkins..... and in the end, she marries him. The MacGregor's consider Mrs. Drummond a loyal member of the family. After her marriage, the now Mrs. Parkins, leaves for the New World with her husband and the Langstons.