Actually, it would be pretty tough not to respond to someone who insults your sister and father in the manner in which Mrs. Dubose does in To Kill a Mockingbird. Mrs. Dubose has never shown friendliness to her young neighbors, Jem and Scout, who pass by her house every day. "Jem and I hated her," a "terrified" Scout reminds us before Mrs. Dubose becomes even more personal with her "vicious" verbal attacks. After Mrs. Dubose insults Scout about her unladylike appearance and her likelihood to eventually be "waiting on tables," she goes after Atticus. She tells the children that

"Your father's no better than the niggers and trash he works for!"

So, it was nearly impossible for Jem not to respond in some way. Although he manages to restrain himself at the time, he later returns to take out his frustrations on the old lady's camellias.

Although Atticus doesn't blame Jem for being "annoyed" by her talk, he calls Jem's actions "inexcusable." He tells Jem that "you can't hold her responsible for what she says and does." At the time, Jem does not understand this, but in time he will. After Mrs. Dubose dies, Atticus explains that her attempts to kick her longtime morphine addiction is what caused her to act so irrationally.

Jem should not worry or respond with anger to Mrs. Dubose's verbal attacks. She is an older woman, likely not completely under control and certainly struggling with aging and pain. Jem should either ignore the painful words she says or if he says something, just say kind words like, "Good evening, Mrs. Dubose."

Mrs. Dubose is addicted to morphine and from an entirely different generation. Struggling with her pain has likely made her grumpy and the kids are easy prey to take her frustration out on.