Who is Lucy Oliver from Second Glance: A Novel and what is their importance?

Lucy Oliver is Meredith's daughter. She can see ghosts, and Cecelia Pike's ghost often comes to visit her. As a result of these visits, Lucy suffers from terrible nightmares that lead her mother to believe she is mentally disturbed. Lucy's fear of ghosts remains until she meets Ethan Wakeman, who helps her get over her fears.