I would recommend the movie "Lady Bird" (2017) for its excellent exploration of sibling relationships. The film follows the complex dynamics between the protagonist, Christine "Lady Bird" McPherson, and her brother, Miguel. The sibling relationship portrayed in the movie is compelling because it authentically captures the love, rivalry, and growth that often characterize such relationships. The interactions between Lady Bird and Miguel provide depth to the characters and add emotional layers to the story, making it a standout example of sibling relationships in modern cinema.