Sign From The Dead

Did a former loved one come back to let the living know that they were ok on the other side through a sign?

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“I guess after that; he started talking about me on Facebook. I found out through a mutual friend. Years passed, we moved on from it. In 2018 I found out he passed away. To this day, I am still not sure how all I know is he died in his sleep. I did hear he became a heavy drinker. It did make me sad, and I was in shock. A few months after his death, I had a dream. I was walking down a street, and my son was in an apartment window yelling out to me that “D” was looking for me. I looked at my son with a look like “how?” when he is gone. I can always only remember bits and pieces of my dreams, but later in that dream, I was lying down, and “D” appeared, and he kept telling me he was sorry.”