Flannery O'Connor is critical for gaining a deep understanding of 『人生の親戚』. Here is the assigned reading, and the order of that reading. All files are on bSpace. If you have not yet looked at the media support information on her, do that first by going here.
1: Skim basic bio on O'Connor at Wiki: Flannery O'Connor (wiki)
2: Skim explanations of the Catholic understanding of Grace: saintaquinas.com | vatican.va
3: Read (and put more energy and care into this part of the reading than any other) two O'Connor short stories, both famous, from the 1950s to 1960, in this order:
A) "A Good Man is Hard to Find"
B) "Everything That Rises Must Converge"
4: Read with moderate care Grimshaw's overview descriptions of O'Connor's work
5: Read Muller on the grotesque in O'Connor's fiction in a way that gives you a sense of his ideas. You can jump around some.
6: Read O'Connor on the grotesque in her fiction. Read for ideas at least through page 816. You can go farther if you wish. (Those working on the grotesque really should read to the end.)
7: Optional — read the first page of Paulson to get a sense of her alternative thesis on how to understand O'Connor. I think it is relevant. You can read the next page if interested.