In my opinion there are not such things as ghosts only demonic entities manifesting themselves any way they like. Nevertheless the only thing that makes them go away is faith the stronger the better. That doesn't mean they ll go away at once they tend to insist on what they like or want to do. I would suggest to bring home a priest on a regular basis and have him read prayers and cleanse the house. If things go worse at first this is because they don't usually like being bothered and they ll try to fight back etc. Another thing you can do if you are a christian is to get yourself holy water in your house spray it and drink a small amount every day.also make the sign of cross before you sleep and each morning you get up before you do anything else. Try to read out aloud yourself anything from the bible especially the prayer that jesus suggested to his followers. Try to do that and see what happens.