I almost forgot about this! I was rereading my post http://www.unsolvedmysteries.com/usm531192.html?t=Mysterious and for some reason this following story popped into my mind.
I have 3 witnesses to this. My husband was still home and we had another couple and their children over for dinner. All the adults were watching hockey in the family room, my daughter had called earlier to say she and the other kids were two streets over playing. The couple finally said they were going home to finish watching the game ...I told them that Mad had called and the kids were playing nearby...that's when we all heard the sound of running footsteps upstairs. It sounded like two sets. I said, oh, they must have come home. I called for them...no answer. So I went upstairs to get them and as it turns out they weren't there, no one was.
When I came down stairs to tell the other adults they were as puzzled as I was because we had all heard the running. I called my daughter and they were still two streets over.