Dear Amy: My father died 20 years ago after a long battle with alcoholism. At the time, he was separated from my mother and estranged from my younger brother. I chose to maintain a relationship with him through the last months of his life when he was suffering from liver failure, and I forgave him for the pain he had caused our family. My brother did not maintain contact, and I completely understand why he made that decision. At my father’s memorial service, a “mystery man” attended. He didn’t come through the receiving line, speak to anyone in the family, bring a card, or sign the guest book. Several of my relatives remarked later that they wondered who he was, but no one had talked to him. He was well dressed and young — maybe early 20s (slightly younger than my brother and I), so not of the age that you would expect someone to show up at a funeral if they were not connected to the deceased. At the time, family members made awkward jokes that I might have a brother I didn’t know about.