Family and childhood
The novel shows childhood in two ways, through Chandin's experience first (primarily), and then through the lens of his daughter. Chandin is a psychopathic and hateful person because, although his life is undeniably complicated and dense with suffering, his behavior is clearly unjustified. He is defined by the fact that he takes his childhood suffering to heart while sociopathically rejecting the humanity of his own children. This makes the novel's depiction of family into a horrifying antithesis; the home is a rape dungeon that the children have no hope of escaping.
Rape
This is a terrible portion of the novel to consider, but this novel does what books about rape often do, which is to force the reader to consider truly heinous sexual abuse against children. The novel is similar in this way to Jaycee Dugard's memoir, except instead of being kidnapped and forced into sexual slavery by a sociopathic stranger (which is already plenty sociopathic), this novel shows a more essential kind of betrayal, the sexual abuse of a father against his own children. He dominates them by rape and fear of rape.
Insanity
The most obvious outcome of Mala's endurance through a childhood and life defined by horror is that she is legitimately insane by the end of the abuse. Her insanity stands up in court as an obvious issue, and she is deemed unable to stand trial for her insanity. Mala's craziness is the product of abuse, so the reader sees this imagery through psychological analyses by the narrator, but the prose, and by the plot itself. The book is largely about the dysfunction that rape instills in childhood victims of it.
The kinsman redeemer
Because of the extreme nature of her story, the novelist includes a kind of deus ex machina. Otoh is the "deus" in question, godlike in Mala's life because he witnesses her sin, decides a judgment about her character, purifies the situation by fire, and vindicates her of her legal guilt. That does not mean she is perfectly able to keep on living her life as normal. The redeemer also does his archetypal job by providing her a future, but a future where she is contained, controlled, and institutionalized.
