Any idea what this dream means?

My grandfather died 13 years ago. Last night I dreamed that he was in the hospital. I was standing in the hospital lobby ( which looked like an upscale hotel. the colors I can remeber are gold and mauve). with my sister, aunt, dad, and grandma (she died this past Christmas eve.) I kept telling it couldn't be him because he died so long ago. My dad just kept saying "It is ok." Everyone else kept saying I was crazy. I told them we went to the funeral but they said that it had been doris's funeral (the only doris I know is a computer system at work). I told them I looked in the casket and that he was dead but they wouldn't listen. I was in a state of panic when I woke up. What does it mean?