Jian Ning (Song Jia), a white-collar beauty working for a Fortune 500 company, and Jiang Xin (Chen Sicheng), a telephone operator at the airport, are a couple born in the 1980s. They have quite different attitudes towards their careers and are about to welcome a new life in their lives. However, this little guy not only involves a lot of energy from the couple, but also affects their work and interpersonal relationships with family, friends, and colleagues, which makes the couple quite scratching their heads. Jian Ning's sister Jian Ai (Wan Qian) accidentally "picked up" a girl from South Korea named Lele (Shimada Runa). Lele's father Yan Daoxin (Wang Yaoqing) is preparing to start a new marriage and is very distressed about this unexpected daughter. Jian Ai, who has a deepening relationship with Lele, is involuntarily involved in the housework of "others" at night. Jian Ai's bestie Zhao Xiaorou (Wang Sisi) and her lover Wu Di (Peng Guanying) finally got married. Facing the little life with innocent eyes flashing, the avant-garde couple who claimed not to have children were also shaken. This is a sonata of life about big children and small children...