2 houses I have lived in that had spirits. I grew up in a house where I have seen 1 spirit walk by me. Knocking on the walls at night, someone turning my door knob etc. Someon walked into my sister's room and sat on her bed at night. I believe that they were there to protect and not to harm. Nothing terrible happened in that house, just protectors.
The first house my husband and I purchased also had spirits. My neighbours said the second to last owners had died of cancer. My children saw ghosts and my daughter had an 'invisible' friend named Lisa to whom she was very attached to and she was very upset when we moved. She wanted to return to the house and live there again. I kept telling her that someone else owns that house now and we got a house where you can have a much bigger room. She was upset for a whole year because Lisa could not come with her, she had to stay in the house. When my son was little, he stood inside of my DH and my room in the dark. When I found him, I asked what he was looking at. He quietly whispered 'ghost'. He was 3. I led him out of the room. There too, protectors. Nothing malicious happened to us.