The biological mother of both Wu Lan and Ma Zhaozhao (identical twins). She was a highly capable coworker of Wan Xiuqin and Wu Feng thirty years ago, winning 'Outstanding Employee' for three consecutive years. Her name 'Yiyi' came from her illiterate family who found 'one-one' simple to write. She became pregnant by a man with gambling debts who tried to extort a 100,000 yuan dowry. She refused to marry him, gave birth alone, and gave one baby (Wu Lan) to Wan Xiuqin and Wu Feng for adoption. She kept the other twin (Ma Zhaozhao), who was later sold by her father after her mother's death.
