Frighten... Nervous...

One of my friends told me a true story that happen on her and her sister. The story began when her whole family moved in a house that was quite old. The first day they move in, they can feel the cold wind that made them felt very nervous and frighten, but they don't think too much. They began to clean and clear the house, but there was something unnormal, the store's door was lock and cannot open. They tried to ignore that door by putting a cabinet in front of it. Their life went as usual everyday, but they still can felt the cold wind. My friend slept next door to her sister and there was a mirror in her sister room's wall that separe the two room. One night, my friend's sister suddenly wake up and saw her sister in the mirror(the bed faced the mirror). She felt very curious why her sister was at her room but when she turned back she was shock because no body was behind her. She was very frighten and cover her blanket tried not to think too much. The next morning she ask my friend whether she wake up or not at that time, her sister said that she really wake up at that time but stay in the room and want to know why her sister knew she wake up. Her sister was shock and told her the true. From that day her sister fall sick for about a month. You know why that thing happen that night? It's because... ... they open that locked store room that morning. So don't open the door as you like.