She Was the Quiet One by Michele Campbell
Twins Rose and Bel Enright are positive that The Odell School is the best move for them — but what they don't know is that the boarding school is known to bring out the worst in its students. Before they know it, the sisters find themselves in an intense rivalry with alarming consequences ending in the death of one of the girls. Was it the act of a mysterious teacher who will do anything to get ahead in his career, or is there something deeper happening at the school that no one is aware of? This enticing thriller examines the extent to which someone will go in order to achieve their goals and the tragic outcome of one sibling rivalry.