In Mary Kubica’s It’s Not Her, the lakeside vacation that should offer calm instead turns into a cramped setting where the Crane family’s fragile power balance grows volatile. The novel traces how uneven control shaped by marital conflict, parental inattention, and rivalry between siblings creates space for dangerous manipulation and secrecy. The book rejects any idea of the family as a refuge and shows a system destabilized by old resentments and competing claims to authority. When outside stress intensifies these tensions, the family’s structure collapses and exposes how easily the myth of a harmonious household can fracture.

The strain between Emily and Nolan Crane shows how an unhappy marriage can infect the wider family. Their exchanges revolve around control; each belittles and tries to dominate the other as they battle over money, daily activities, and how to parent their children. Nolan’s unemployment leaves him raw, and Emily criticizes him with remarks like her jab about working at the Gap despite his MIT degree. Nolan responds with irritation, telling her that “This trip would have been a lot more fun if you just stayed home” (18). Their steady hostility shapes Emily’s attempts to manage Reese. Emily’s attempts to guide and discipline Reese are undermined by Nolan’s lack of support, and the constant fighting with Nolan leaves her little energy to really attend to her children. She has no idea what is happening in Reese’s life or how troubled her son, Wyatt, really is. Reese reacts to Emily’s insensitive parenting with open fury, eventually shouting, “I hate you. I wish you’d die” (54). The narrative links these moments and shows how the parents’ struggle for power spills into the children’s emotional lives.

Reese’s exchanges with her brother, Wyatt, echo the same patterns. The two argue constantly about Wyatt’s efforts to control Reese. He uses her secrets to extort her and treats every slip as an opportunity for profit. After Reese briefly loses Mae, Wyatt demands money to stay quiet. Later, he trails Reese when she sneaks out to meet a boy and announces, “Forty dollars or I tell” (155). His behavior grows out of the family atmosphere around him. Because his parents treat him as their “golden child” and refuse to see clear evidence of his wrongdoing, Wyatt never has to face the consequences of his actions. It is never made clear to him why he should not use information against his sister in the same way he sees his parents using information against one another. His blackmail shows a younger generation already replicating the emotional battles that shape their household.

Courtney and Elliott’s marriage looks steadier at first, yet their conversations also reveal subtle contests over truth and interpretation. After the murders, Courtney studies the blood on Elliott’s shoes and asks about it. He first claims it came from the fish he bled. Then he shifts and says it could be his own blood. When she presses him, he replies, “You didn’t have to turn it into a whole thing” (235). Elliott’s deflection shakes her sense of what she saw and reinforces his control over how events get framed. That such a small thing is enough to shake Courtney’s faith in her husband shows that their marriage is not as rock-steady as it first seems. Later, Courtney shows her lack of trust in Elliott when she finds unsettling photos and a puzzling internet search on his iPad. She does not simply ask him to explain—instead, she leaps to the conclusion that her husband may be a killer. Through these overlapping relationships, the novel shows how both open aggression and  quieter manipulation erode trust and prepare the ground for disaster.