What is a short summary of the story, Compassion, from the collection, Trash: Stories?

In the story, Compassion, the narrator’s mother is dying of cancer. While her mother has had cancer on and off for decades, the narrator and her sisters, Arlene and Jo, know she will not survive this time. In the story, the sisters deal with the childhood abuse from their stepfather, Jack, the distance between them, and the fear their mother feels as she slips from life.