My 6 year old son has woke up in the middle of the night and saw his toys moving around? My 4 year old son shares the same room and says there's something in his room. But I don't know what?
Last night I woke up at around 3 and hared a very strange crying sound and shuffling, out side my bedroom then you could hear the walking down the corridor and living room. It was crying constantly and weird...

Did you get up to investigate? I know it's hard to take sometimes, but next time one of your children says something is in their room... go in there and see what's going on. Ask them if it is still there while you are. Have you been in the home long? How long have your children been claiming these things? It is possible one child may be making the other one think something is going on. But, it could be real as well. Time and further investigation will tell. If you want to know the history of the home, talk to some neighbors... do some research at the library. Not that something HAD to have happened in your home, but sometimes it can be a clue.