There are numerous similarities between Holden Caulfield and Jeremy (Jem) Finch. Both are white boys, but Holden is 16 during Catcher's two days of action, and Jem is about 13 when Mockingbird ends. Both come from upper-middle-class professional families in which the parents are a traditional heterosexual married couple, both also presumably white. Holden's family is wealthier than Jem's. Both of Holden's parents are alive, but Jem's mother passed when he was small. Both boys currently have one sister a few years younger of whom they are fond and toward whom they generally feel protective, although they sometimes treat their sisters unkindly. Holden's other sibling, a younger brother, died a couple of years earlier. Thus, one of the most striking features the boys have in common is that they have survived the loss of a close family member at a very young age.

Holden studies at a private boarding school, while Jem attends a local public school. Holden's father seems overly occupied in his work, possibly to distract him from grief. Jem's father is usually home but must often travel for work, and an African American housekeeper also provides childcare until the Jem's aunt moves in.

Both boys have difficulties with adolescence. Holden is grieving for his brother and underperforming at school, where he is bullied by an aggressive roommate. Both boys are intelligent, with Holden apparently more intellectual and Jem analytical in a lawyer-ish way. Both boys sometimes use violence to express their feelings. Holden seems more likely to harm himself.

While Holden intrudes on his sister's privacy, reads her private papers, and plans to take her savings and run away, he never physically harms her or verbally abuses her. He wishes to protect, or "catch," younger children. Jem is often mean to his sister, belittling her and excluding her from play, and several times is physically violent, pushing her into the road inside a tire, pulling her hair, and kicking her. Ultimately he does protect her from an attacker, suffering a broken arm in doing so.

Jem shows more growth because his character is shown to develop over several years, and perhaps because he is at a younger stage of development.