Family of Origin by CJ Hauser

This is a book that illustrates the cascading effect of trauma across generations in families.
Estranged half-siblings 35-year-old Elsa—a discouraged second-grade teacher in Minnesota—and 29-year-old Nolan—a social media manager for the San Francisco Giants—travel to Leap’s Island, a private island off the Gulf Coast, to investigate the drowning death of their father, Ian Grey.
The reason that they are estranged is because Elsa initiated an inappropriate relationship with Nolan when he was 13 and she was much older.  Prior to this, Elsa took the brunt of the blame, which she certainly played a part in, but her parents set her up to fail, and fail she did, in a spectacular manner.
The eccentric inhabitants of the island are a perfect back drop for the siblings to try to move forward from their abruption.  The islanders jealously guard their research on the island’s unique duck species, hoping to be the first to prove the theory. Elsa is convinced Ian committed suicide, but Nolan hopes conversations with the researchers will prove her wrong.  At the end they take a step forward into their future.  Very good read.