Got one from my son when he was about 3 or 4. He can fill in what I miss.
He used to wake up in the middle of the night and come in to mine and my wifes room. He'd wake us up. He told us that the people in the walls where making too much noise and he wanted me to shut them up. I'd go in there and play the father role and tell the people in the wall to shut up so Brad could sleep. He'd get back in bed and either myself or my wife would stay with him until he fell asleep.
One night he woke up screaming. I ran in and he was sitting up in bed and was looking at the one corner near the ceiling. He was terrified. When we calmed him down he told us the people in the wall were trying to steal him. The tried to pull him in the wall. When he screamed they stopped, but, he said they were watching us when we were trying to calm him.
The next day we moved him into my daughters room and moved her into Brads. Bridget was 7 or 8 at the time. The second night she is in the room she woke us up and said she was hearing footsteps in the ceiling and in the walls. She also said it sounded the loudest in the closet. At this point, since I do think there are unexplained things, I am starting think something is wrong.
We moved her to spare bedroom and closed off that room until the weekend. The weekend came and I slept in there. About 2 or 3 in the morning I hear what sounds like people walking in the ceiling. It goes on for a couple hours.
The next morning I go get one of my friends and we start to gut the room. It didn't take long to find the cause. A racoon had dug his way under the front eves and into the closet. From there he had access to the whole room. He invited in his family. There was this huge nest in the ceiling. He was confined to just that room, but, there were signs of him trying to expand his domain. We fixed the hole he made and checked the outside roof line of the whole house to make sure there were no other attempts to get in.
Once secured I called the local drywall guy so he could come and put the room back together.