How does the description in paragraphs 8-10 shape your perception of the narrator's relationship to his brother? What does it help you infer about his decision to write this piece

8. Up until then my brother had never shown any emotion to me other than disdain. He had never asked me anything, unless it was a demand, an expectation, an obligation to be his throwaway boy-doll. But for this once he looked at me, tears welled in his eyes, blood streamed from several cuts—lips and cheeks swollen.

9. “Swear—you got to swear—you'll never tell anybody how I cried,” he said.

10. I suppose I did promise. It was his one last thing to hold onto, his rep as someone who could take a belt whipping, who could take a beating in the neighborhood and still go back risking more—it was this pathetic plea from the pavement I remember. I must have promised.