The Uninvited (2009)

Teen Anna has spent the last 10 months institutionalized to deal with the trauma of her mother dying in a fire on the family property in coastal Maine. Her bedridden ill mother was staying in the small cabin down by the water. Anna has a recurring nightmare of the night of the fire, the kind that is slightly different every time. Upon her release and her return home, Anna discovers that her father Steven, a famous writer, is now in a relationship with Rachel, his late wife's former private nurse, and she has moved into the house. Now Anna has a different series of nightmares, most of seemingly dead people including her mother. She doesn't know if these visions are real or just her imagination, but she comes to the conclusion that her mother is trying to tell her something; as the nightmares progress, she thinks that the message is that it was Rachel who killed her. With her father seemingly on Rachel's side in his love for her and his intention to marry her, Anna is only able to convince her older sister Alex that Rachel killed their mother; having felt abandoned and having to deal with their father and Rachel on her own in Anna's absence, Alex is easily convinced. And Anna's former boyfriend Matt seems to imply that he can confirm their suspicions--he actually saw what happened that night. As Anna and Alex launch a serious investigation to discover not only what happened but also Rachel's end goal, they may not be prepared for Rachel's tenacity and determination to protect the castle she's built at any and all costs.