I'm generally sceptical about paranormal stuff for exactly this reason - there are billions of people, and no solid evidence that stands up to scrutiny by independent outsiders.
I have no doubt that people who have been haunted (for want of a better word) have had a genuine experience, but that it was the unquiet spirits of the dead is beyond my own experience and understanding.
I'm not saying it can't happen, but I'm saying that I've seen no evidence that I can feel confident in.
That said - if Shanni needs someone to stay over while she looks for the ghost, I'm there.