Do you believe in ghosts?

Anyone else watching The Secret of Crickley Hall on BBC1? It's a 3-part tv-drama based on the work of James Herbert. When the two-year-old of a couple disappears, the wife breaks down and her husband thinks she'll find relief in other surroundings. So he seeks a job elsewhere and rents an abandoned old house for the time being - Crickley Hall. What he doesn't suspect is that both his wife and his two daughters see a ghost - the ghost of Augustus Crippen who used to possess the house when it was an orphanage.

Now as an author is can quite go along with this story, but I don't believe in ghosts. I can write about them, but never expect to see one in person. I've been to many places, and never seen an apparition of any kind beside human beings.

My sister, on the other hand, would not be so sure... She is more psychic than I am, and she sometimes has premonitions. She feels actual pain when someone in our direct family circle is about to die. She felt it when my grandfather died of a brain stroke, when my grandmother was into hospital for a simple flu, when my dad went to have his yearly checkup (and died of a heartstroke in the hospital), and finally when my mother was ill. One day, she told me something was about to happen and a couple of hours later our car slipped and we nearly crashed. Finally, after having made an emergency landing with a plane when flying to New York, she told me afterwards she had known there was 'something' but we would survive.

She also claims to having seen the ghost of our mother more than once. Apparently, she sees her walking through the house. The first time, mother even told her she was happy where she was now and we should not feel bad about her not being there anymore, as she is watching over us.

Believe it or not. What's your take?