Who pities the world's loving mother

Six-year-old Xiao Haiyan lives with her father Dayong and mother Jinhua in a seaside town. In Haiyan's eyes, her father is the best person in the world, but in fact, Dayong was actually married before and had another daughter. He has been hiding the truth from Jinhua and secretly taking care of his ex-wife and daughter. His ex-wife got leukemia, and Dayong had no money, so he had to steal factory goods and sell them. Jinhua knew the truth, was furious, and had a big fight with Dayong. Dayong went to sea with the ocean cargo ship, hoping to earn some money to fill his vacancy. Just after Dayong went to sea, the condition of Dayong's ex-wife worsened, and the hard-hearted Jinhua went to the hospital to take care of her. Before she died, her ex-wife entrusted her daughter Haijun to Jinhua: "You are a good person, and you will be good to her." Jinhua tearfully agreed to her last request before her death. Jinhua took Haijun home and asked Haiyan to recognize this sister. She took her two daughters alone and waited for Dayong to return from the sea. What she waited for was bad news: the ship lost contact and Dayong's whereabouts were unknown! A few years later, Haiyan Haijun has become an eleven or twelve-year-old middle school student. She is tall and graceful, good at singing and dancing, and is the star of the school. Jinhua pushes a cart to buy fish balls all day long, and works hard to take care of the housework. Based on her ignorant childhood impressions, Haiyan believes that her mother forced her father away, so she always opposes her mother. On the contrary, Haijun is considerate of her mother.