Who is Tess Mercy from Montana Sky and what is their importance?

Tess is Jack Mercy's oldest daughter. She is a beautiful woman who lives in California, working as a screenwriter. Tess has no use for Jack, as he is the man that cast both herself and her mother aside when she was a child. Tess expects some type of inheritance, but is stunned when she learns that Jack Mercy's will states that she must live in Montana on the ranch for one year. Tess is willing to leave with nothing until she learns that her share of the estate is worth around six million dollars. The money makes the sacrifice worth it to Tess, though she appears not to care for either of her sisters. The reader learns that Tess does have a soft heart and she does care, especially for the wounded Lily, but she feels that putting up a disinterested front will keep her heart safe.