A few years back my uncle, his ex wife, and her 2 kids lived in a house somewhere in Anne Arundel Co. The youngest child starting talking about this little boy. They chalked it up to her having an imaginary friend. Well my uncle put the kids to bed one night, and went downstairs. He saw, what appeard to be, a child hiding behind the long curtins in their living room. He thought the youngest girl had gotten out of bed and was hiding. He said "Didn't I tell you to go to bed?" and walked over to the curtains, pulled them open, and there was nothing there.
Another incident he was coming down the stairs, and looked in the mirror next to the front door that you could see into the living room (around the corner). He said he saw a young boy who appeared to have some severe head trauma. He got to the bottom of the steps, and looked into the living room, and there was nothing there. It really freaked him out. I know by the time they moved out, all 4 of them had some encounters with the boy.
He said there was a mound of dirt in the crawl space of that house, but wouldn't dare mess with it!