Can a part die?

The first time my dead alter appeared I was 18 and I thought I was possessed by a spirit of a dead wolf. I didn't know what to make of this apparition in my mind but he became a part of me. In time I told him he was dead and it's time to go to the other side. He became a corpse in my mind and then went dormant for many years.

More recently I was looking for a reclusive alter named T who used to be in the front. The wolf responded, that's why I think the wolf is T's alter. I don't believe it was literally life-threatening abuse or neglect that caused the dead alter, but it was very early events that made me not want to live on this planet and be a human.