Final answer:
The 'day after day' repetition emphasizes Whitehead's unwavering determination and potential obsession with his pursuit, highlighting his persistence in a possibly consuming task.
Step-by-step explanation:
The phrase 'day after day' helps to convey the perseverance, determination, and possibly the obsession of Whitehead's personality. It suggests a relentless, repetitive effort, indicating that Whitehead is a character who is steadfast in his actions and possibly consumed by his quest.
This could reflect a deep sense of duty, a personal mission, or an inability to disengage from his task, which shows how committed—or fixated—he is on tracking down the residents.