In "Manchester by the Sea," Lucas Hedges portrays a teenager named Patrick, who grapples with the emotional fallout of his father's death and his strained relationship with his uncle, played by Casey Affleck. The film explores themes of grief, loss, and the complexities of familial bonds, showcasing how Patrick navigates his feelings towards his father and the impact of their relationship on his life. Hedges' performance captures the struggle of a young man trying to find his place in a world marked by tragedy and unresolved emotions.