Like many adolescents, Jem is idealistic. Even after Atticus' long explanation about the intricacies of the Tom Robinson case, Jem is unable to accept the jury's conviction. In fact, he is ready to overhaul the justice system and abolish juries all together. Wisely, Atticus doesn't try to squelch or minimize Jem's feelings; by respecting his son, Atticus allows Jem to better cope with the tragedy. Still, Jem turns on Scout when she tells him about Miss Gates' racist remarks at the courthouse, shouting, "'I never wanta hear about that courthouse again, ever, ever, you hear me?'" His coping skills are still developing, and his family is the one group that gives him the room that he needs to hone them.
Ironically, Jem, who so strongly identifies with Tom Robinson, is the only person in the story who is left with physical evidence of the whole event. More ironic still is the fact that Jem's injury leaves "His left arm…somewhat shorter than the right" just like Tom Robinson's, and Tom Robinson sustained his injury at approximately the same age. That the man responsible for breaking Jem's arm was also responsible for sending Tom to prison (and indirectly, responsible for his death) serves to drive the irony home.
The adult Jean Louise doesn't provide much insight into the adult Jeremy Atticus Finch, but from the fact that the story begins with their disagreement over when various events started, the reader can assume that they maintained a similar relationship into adulthood.
