Why did Officer Charles stay at Ma Charles house in the book "Gone Crazy in Alabama"

In the book "Gone Crazy in Alabama" by Rita Williams-Garcia, Officer Charles stays at Ma Charles' house because he is conducting an investigation regarding an incident that occurred involving the Gaither sisters. The Gaither sisters, Delphine, Vonetta, and Fern, are spending the summer with their grandmother, Ma Charles, in rural Alabama. Officer Charles stays at the house to gather information and interview the family members about the incident, which becomes a significant part of the story's plot.