There are so many things we don't understand about life.... and death.  I would not be surprised that if the truth be known there is a kindred spirit living in your home.  Who knows 

, but if it was an evil spirit, you'd probably know by now. 
We built our home on what used to be a cotton plantation and before that was inhabited by Cherokees.  I am convinced that our home is built over an ancient burial ground of sorts.