Answer:
Brian matures through his new ability to be patient. Setbacks that would have immobilized the "old Brian," the Brian at the start of the novel, later become manageable. He learns to control his temper when he realizes that his frustration and hopelessness does not help his family situation.
Step-by-step explanation:
Or you could say... Brian matures through his new ability to be patient. Setbacks that would have immobilized the "old Brian," the Brian at the start of the novel, later become manageable. He learns to control his temper when he realizes that his frustration and hopelessness does not help his family situation.