[dragoneyes]

My father has been telling me recently that for the last month, about 3-4 times now, a light has switched on (a dimmer at full blast) by itself in the middle of the night, and then another light in a different room a few weeks later.
He was watching tv one night and then channel changed by itself in front of him.

My grandma passed away in December. I lived in that house all throughout my teen years and he has lived there for 10 years and never has any of that happened.
My mother passed away when I was a child and nothing like this ever happened, no sign of her spirit around him or me.
Just a coincidence or a sign of my grandmother's presence in his house? I just find the timing a bit odd.
Whats weird though is my father wasn't all that close with my grandma, but I certainly was. I haven't experienced anything in my apartment like that (good thing because I'd probably freak)
Of course could just be an electrical malfunction perhaps but with the timing, are these common paranormal occurrences?