I have had a few visions in my dreams over the years. I decided to condense the most explicitly clear ones here. Hope you enjoy, and feel free to share your own visions, too!
Note: I was raised in a Christian household, so the stories from my childhood were assumed to be from the Judeo-Christian version of the afterlife.
Dream of my birth mother: I was adopted as a baby, and have never met my birth parents. I wasn't informed of this fact until I was seven years old. However, when I was four, I had a dream of a woman in a purple dress who looked startling like myself. She didn't say anything, just smiled at me. I woke up, and casually told my mother later that day that I, quote, "Had another Mommy who lived in Heaven." Obviously, my mother was shocked, terrified someone had told me the truth.
Dreams of my deceased grandmother: Almost two years ago, I lost my maternal grandmother to brain cancer. I was the last person to say goodbye to her; she literally refused to die until she I would be at peace with her passing. My family was deep in grief for a while. Then, a few months later, I had two dreams about her. The setting and premise was the same: I would go into my Gran's room, and she'd be sitting there in her chair, white light pouring through her window. We would sit and talk; I got to give her a proper goodbye and tell her how much I loved her. And as my grief began to subside, so did the dreams. It's worth noting that my mother also had these dreams.