Although Holden’s younger brother, Allie, dies of leukemia three years before the beginning of the novel, his loss profoundly weighs on Holden. To Holden, Allie’s death signifies the unfairness of death, the fragility of life, and the loss of potential. He even hates the idea of people visiting Allie’s grave because the visitors get to leave and go home somewhere warm, while Allie never will. Holden idealizes Allie, calling him a genius and the nicest person in his family. By focusing on how good Allie was, Holden emphasizes how unfair it is that Allie, of all people, has died in a way that no one could have changed or prevented. For example, Holden comments that Allie’s teachers always called him a pleasure to have in class. With Holden narrating his story directly after being kicked out of school, it’s possible to read survivor’s guilt into this statement. Where Holden is failing, Allie, he believes, would have been successful. Holden’s grief is both from him missing his brother and this profound illustration of the finality of death. Death comes for Allie even though he’s a great kid.

Allie’s death is intimately tied to Holden’s suicidality. At first, it seems Holden’s grief over Allie’s death contributes to his suicidal ideation. Immediately after Allie dies, Holden punches out all the windows in the garage, breaking his hands in the process and ending up in the hospital, a clear act of self-harm. Holden lists Allie as one of the few people he likes, concerning Phoebe that the only person he’s willing to list is dead. However, Allie’s goodness also acts as a driving force for Holden to stay alive. When he walks in the cold of Central Park after his date with Sally, the memory of how his family still grieves for Allie encourages him to go to his house and see Phoebe instead of succumbing to hypothermia. After leaving Mr. Antolini’s house, Holden imagines Allie watching over him, keeping him from disappearing. Thus, as a reminder of how fragile life is, Allie also provides Holden a reason to keep going.