This true account actually happened to a friend of mine.
One night she found herself alone in the house. Her mother had gone to work for the night and her brother was out with his girlfriend. There were only two other living creatures in the house besides her, her two dogs, which were locked in her room with her.
While she was working on a school assignment, she heard what sounded like footsteps walking up and down the hallway. She froze and looked out the door to find nothing at all-no one could have possibly been responsible for making them. She shut the door again and resumed her work. About a half an hour later she heard the footsteps once again, beginning in the living room and coming to her door. All doubts of her hearing things were denied when her two dogs stood up, the hair on their backs rising as they growled at the door handle. The footsteps retreated back to the living room. With that my friend grabbed her keys and got out of her house as quickly as she could and fled to my house to tell me the story and ask me if I would go back to her house with her. I say, sorry, your are welcome to stay here but I am not going to a haunted house!
She stayed at her house until her brother returned from his date, and told him about it. He didn't believe her, and tried to pass it off as "the house settling."
About a week later she was in the kitchen getting a glass of milk, alone once again. From her basement she heard a distinct human whistle. She stood in her place and listened for more to try to distinguish what it was. Shortly after whispering of some garbled sort followed in the basement. Once again the dogs heard and looked around the kitchen confused.
After some later research, my friend discovered that a little girl died in the house after a fall down the stairs. A few weeks later her mother reported to her that when she was alone, she had heard footsteps and voices, too. I will never go there again!