Rain (2006)

Rain, a young black musical prodigy, finds trouble and heartbreak when she witnesses her sister's murder by gangbangers. In order to protect her daughter, Rain's mother secretly contacts Rain's biological mother, and Rain learns the truth of her parentage: She is the daughter of a white socialite. Sent to live with her wealthy grandmother, Rain adjusts to boarding school life, where her musical talents flourish.

Unfortunately the movie Rain is not yet available on HBO Max.