I'm not woo but talking to my sister this weekend made me think.
We grew up in a Victorian house and would see a lady walking around in a long black dress when we were very little. I don't remember her but my sister does and says she used to smile at her around the bedroom door.
A family friend came for dinner once when we were older and at the dining table was pale faced and said he had seen a lady in a long dress walking down the hallway.
I am a bit sceptical of ghosts but it seemed odd that more than one person had seen her. Anyone else seen an apparition more than once?