How is the narrator's response to Sonny shaped by his own set of goals, hang-ups, and responsibilities as his "brother's keeper"?James Baldwin's...

In James Baldwin's "Sonny's Blues," having had a daughter
die, the narrator notes that "[M]y trouble made his real."  As he waits for Sonny at the
subway station, the narrator experiences a flood of memories hit him and he finds
himself shaking hands with "the baby brother I'd never known."  After the narrator picks
up Sonny, they ride in a cab through the "killing streets" of Harlem until they reach
his home:

The
moment Sonny and I started into the house I had the feeling that I was simply bringing
him back into the danger he had almost died trying to
escape.

Again, the narrator
is struck by memories, recalling his promise to his mother:  "I won't let nothing happen
to Sonny."  Significantly, he also recalls her other words,"But you go to let him know
you's there."  Now he senses himself "in the presence of something"
as he looks at Sonny as more memories press upon him: the time Sonny lived with him, the
constant playing of the piano--"it was like living with sound"--and how wearing it was
on his family.

One day Sonny returns to his brother's
house, but pauses outside at a street revival and listens.  When he crosses the street,
the narrator, who has been watching apprehensively at the window remarks upon Sonny's
musical walk that he has "never really noticed before."  After Sonny comes in, he tries
to converse with his brother.  When Sonny says that the singer's voice reminded him for
a minute of what heroin feels like sometimes, the narrator reacts as his voice is "very
ugly, full of contempt, and anger."  However, as he listens to the poignancy in Sonny's
voice as he comments on "how much suffering she must have had to go through--to sing
like that," and his attitude changes as he seeks communication with a brother with whom
he has not had a close relationship.  As Sonny's confesses, the narrator truly listens,
recognizing the darker side of himself, a side he gets to know as he sits in the dark of
the nightclub where Sonny plays. And, it is then that the narrator sheds his opinions,
his own sets of goals, and his biases.  Instead, he listens to Sonny play the blues.  He
hears Sonny release the "storm inside" himself.  "And his triumph, when he triumphs, is
ours" the narrator comments as he watches Sonny's face which has the "fire and fury of
battle occurring in him" along with the light that comes from the listeners who
understand. 

Sonny triumphs because he releases the storm
within him; likewise, the brother triumphs as he listens to Sonny and understands him
and witnesses something sacred, "the very cup of trembling" of Sonny's
troubles.