How does The Girls in the Garden use ideas of home and exile to develop the mystery?

The garden at the center of Virginia Park is surrounded by buildings. How does this make it more representative of nature, or less connected to a greater natural world?

Some of the parents in The Girls in the Garden shirk their responsibilities to their children. How would you compare and/or contrast the responsibility of the non-parental adults in the novel, such as Rhea or the police officers, and the responsibility of the parents?