My brother also had a couple of friends over one day when it was just them and me. They were playing video games in his bedroom. I was about 12 years old at the time and over the whole 'ghost thing' so I had the courage to read a book in the living room alone. I started hearing a knocking sound. At first I thought it was my brother and his friends upstairs banging on the walls or acting stupid. So I ignored. A few minutes later, I started hearing it again. I yelled up to the boys to be quiet. No one answered, so I just went on about my book. Then I heard it again and so I put my book down on the fireplace mantel and when upstairs to yell at my brother and his friends to stop banging things around. When I got there, they hadn't been doing anything of the sort. They said that they stopped playing video games and started cramming for the big test that they would all take the next day. So all they had been doing was reading books for the past hour.
I didn't know what to think. Then I remembered all the crazy things that had been happening, and realized it must be the ghost. I didn't tell his friends though because I didn't want people to stop coming over to our house for being too scared again. So I casually walked down the stairs to find my book on the floor. No one had moved it. I had been the only one in there.
There had been several other little incidents that occured in that house. But maybe next time. I hope you enjoyed it! I sure didn't!