My grandmother had a cross on the walls of every room except the bathroom. When I got old enough, I asked her why and she said it was because of "the visitors." We'd actually hear her in the hallway or downstairs arguing with what sounded like an angry woman, and telling her to depart from whence she came.
One day me and my older sister worked up the courage to head downstairs in the dead of night. There, we witnessed grandmom being ordered out of what this entity considered tobe HER house, which of course she refused. Upon ordering the spirit to leave in the name of Jesus, it did.
Turns out a woman had been murdered there over 100 years ago, and didn't want to move on. After all, it was her house.