Who is Mrs. Yun in the novel, Almond?

Mrs. Yun is Gon's mother and Professor Yun's wife. When her son is just four years old, Mrs. Yun loses him at an amusement park. The tragedy swiftly ends Mrs. Yun's career as a successful journalist. She becomes consumed by despair, eventually falling terribly ill. Just before she dies, Yunjae agrees to visit her in the hospital, posing as her son. Later, when Gon asks about her, Yunjae tells him she looked like Gon, and that her hands and hug were warm.