I think the first time I dreamed of my dad again he got into a swimming pool and died in there right in front of me with a ton of blood floating out of him, so that wasn't great. After that they tended to be better, like he had been working away, but had come back. Eventually even in the dreams my mind fully accepted that he was dead, and that these times I get to spend with him should just be enjoyed, I remember him liking a model I had built (in real life that day), and another time just before I got married I dreamed he was sharing a drink with me and my future father in law and they were getting on great.
My brother died aboard after he emigrated to Spain, I didn't go to see him before he went, which I regret, but I wouldn't have liked to see him suffering.
One of the last things he said (so my sister in law tells me) is when he could no longer see the people around him, was "no dad, I'm not ready to come with you"
I believe we see those we have lost again when its our turn to go, and the best thing about this belief, is that if I am wrong, I will never know.