What role does music play in the short story and how does music help the speaker understand his younger brother?

Sonny has a lot of problems. Through addictions,feelings of isolation and loneliness, Sunny always has his music. The Blues, by it's very title, seems to help people who are feeling blue. This is the case for Sunny. Baldwin gives Sunny the talent to play the blues/Jazz which seems to heal him or at least dull his emotional pain, "Sometimes you'll do anything to play, even cut your mother's throat." He laughed and looked at me. "Or your brother's." Then he sobered. "Or your own." Music also gives insight into his relationship with his own brother. Sunny sees that they both can't communicate because they operate in a different emotional language. Ironically it is only through the filter of song that Sunny can interpret his brother.