He had won her back, little by little…Years of truthfulness, years of love, all undone by a simple switch
-- Narration (Prologue)

Importance: This line of narration occurs just after Angela's discovery that Grant has been having marital infidelities once again. This line of narration emphasizes the rift that this discovery causes, and thus the security of Grant and Angela's marriage is threatened by this rift as well as by the trauma of Caitlin's disappearance.

You could not imagine burying your children—putting their bodies into the earth while you went on living, growing older—until you had buried one.
-- Narration (chapter 8)

Importance: This line of narration articulates Angela's thoughts and feelings as she struggles with the emotional impacts of having possibly lost Caitlin forever. Caitlin's disappearance is deeply traumatic for all of the Courtlands, and this moment helps to emphasize the overall narrative focus on the effects of this trauma as definers of the Courtlands'...