Li Lingyue, an adorable little girl raised in the countryside, suddenly arrives at the Li family home in the city and becomes the family's heir. Guan Wan'er, the adopted daughter who has always been cherished, struggles to accept this change. Gradually, however, the two girls overcome their distance and become close companions. The three Li brothers also learn to protect their little sister as they spend time together. Through everyday laughter and family troubles, everyone learns to get along, heal one another, and find warmth and joy in their lively family life.