Who is Brenda Wright Lafferty from Under the Banner of Heaven: A Story of Violent Faith and what is their importance?

Brenda was the woman murdered by Ron and Dan Lafferty when she was 24 years old. Brenda was the wife of Allen Lafferty and the mother of Erica. Although Brenda worked hard to keep her marriage together she admitted to others that she realized shortly into her marriage to Allen that she had made a mistake. It was at this point that she realized how unusual the Lafferty family's religious beliefs were. In fact, at the point that her baby becomes sick and Allen will not let Brenda take her to the doctor, Brenda believes her in-laws are evil.