Watch Music (2021) online

Music, directed by Sia, tells the story of Zu (Kate Hudson), a young woman who, after solving her alcoholism problems, receives an unexpected news: she must take care of her teenage stepsister Music (Maddie Ziegler), from autism. The girl does not speak and expresses herself exclusively through music and isolates herself with her headphones.
Despite her initial problems, Zu will be able to bond with her sister, who will begin to express her emotions. Music, in fact, hides within itself a fervent fantasy, which transforms the world around her into colorful musical numbers, of which the people closest to her are the protagonists.