Who is Stepha Odell from A Great Deliverance and what is their importance?

Stepha Odell is the owner of Keldale Lodge. Her twin brother, Paul, was at one time married to Olivia Odell. Stepha is Bridie Odell's aunt. Stepha is approximately forty years old, tall and very shapely. She has shoulder-length coppery red hair. At one point, Stepha gave birth to a child fathered by Ezra Farmington. Stepha is a carrier of Huntington's disease and because of this, she refuses to marry or have anymore children. Stepha is lovers with Richard Gibson, William Teys' nephew.