In Liu Cixin's science fiction novel," The Three-Body Problem," Ye Wenjie was an important character. Her actions and decisions had a profound impact on the entire story. Ye Wenjie and Yang Dong met and fell in love during a scientific experiment. However, due to Ye Wenjie's personal beliefs and ideas, she finally chose to leave Yang Dong to continue her scientific research. After she left, Yang Dong had been thinking about her silently and trying to find Ye Wenjie's whereabouts. However, Ye Wenjie left a letter before she left, expressing her guilt and apology to Yang Dong and saying that she did not want Yang Dong to know about her past. Because of Ye Wenjie's actions before she left, she caused Yang Dong's death. Yang Dong's death was caused by a series of events and accidents, not by Ye Wenjie's direct actions. Therefore, from the plot of the novel, it could be said that Ye Wenjie directly killed her daughter, Yang Dong.