Teacher:Generate a correct and concise answer for the question based on the words in the context.
Teacher: Now, understand the problem? Solve this instance: Context : When Liu Qi died shortly after Liu Bei secured his position in the area, the latter succeeded the former as the new governor of Jing Province, and went to Jianye to marry Sun Quan's younger sister Lady Sun in order to legitimatise his succession.
Question : What is Liu Bei's spouse's name?
Student:
Lady Sun