First idea for trailer synopsis

The idea for our horror film is based on a girl who sleep walks around her house at night and day by day her parents get more and more worried because she starts doing stranger things and it starts to get dangerous, for example innocent things like leaving a draw open develops onto her waking up with a knife on her pillow. At this point the parents decide to take action and place security cameras in her room and around the house, night by night the mum and dad notice more worrying things happen such as writing on walls and other wierd occurences. They get even more worried when the mother finds a diary underneath the floor boards in her daughters room while cleaning it. The diary is from the previous owners of the house and when reading it she finds out that the previous owners daughter sleep walked too and the further she reads, the more diverse the evens get. She gets really worried and decides to bring an expert in paranormal occurrences into the house and have a look at her daughter, he talks about spirits in the house and how something isnt right when he is around her and gets a weird aura. When the expert leaves the problems escalate even further, and the daughter ends up killing her parents.