Who is Xu Yourong's grandfather?

Grandfather is Professor Lao Xu. Xu Yourong's grandfather and father both had children in their early thirties. Therefore, when Xu Yourong was born, his grandparents had retired at home. Grandpa Xu is a professor in medical college. Before retiring, he was the president of the affiliated hospital of Kyoto University. He retired at the age of sixty-five, and he was not used to enjoying his leisure immediately. On weekdays, he grows flowers, raises fish, practices calligraphy and plays chess, but he can't make up for the emptiness in his heart. When Xu Yourong was born, her parents were busy with their careers. They were very worried about taking care of her, so their grandparents.