There was this one time when we had a family reunion. There were many people there and my mom told me to sit down on a spot. I told her that I couldn't because grandpa was sitting there. She said grandpa has been dead for 3 years now...
I was confused because I could see him sitting there. He didn't move, but he was there. My mom made me sit down and drink something. After a while he was gone.
I think it was a hallucination though, because I'd taken 3 painkillers of which you're only supposed to take one. And well... dead people are... dead....