This is Harriet Poster

This is Harriet: Directed by Robin Weigert. With Josh Hamilton, Elvy, Roberta Maxwell, Jennifer Taher. Allison, a pianist whose mother suffers from dementia, has been led to believe she's been selected by the parents of a young prodigy to play their son's concerto. She quickly learns, however, that her potential employers are deeply conflicted over what's best for the boy. The prodigy's father refuses to believe his wife's superstition about the source of a mysterious affliction that causes the boy to be beset by memories from someone else's life. Allison has an emotional breakthrough when she finally submits to her mother's belief that she is the mother's late sister, Harriet; an experiment that ends up ruining her prospects with the family.