Guandong girl Su Ziyue suddenly learns that she turns out to be the true eldest daughter swapped at birth in the capital city. Leaving the breeding farm full of laughter in her Guandong hometown, she comes alone to the Su family and finds that her biological younger sister Su Yuqiao developed autism due to being kidnapped in childhood, having not spoken to anyone for ten years. The family lives in guilt and distance, separated from each other by a thick shell. Su Ziyue uses the warm enthusiasm deep in a Guandong person's bones to pry open her sister's shell bit by bit, and also pries open the relationship of this family that has been frozen for ten years. She helps her elder brother see his girlfriend clearly, helps her mom and dad regain the courage to speak to each other properly, and under her mediation, the two families become one family, and both girls harvest double family affection.