In ancient times, medical conditions were limited, and the child mortality rate was already high. Because of their special status, the prince and princess have to register their births on Yushu, and their deaths will be registered in detail, which will give people the feeling that they are easy to die young. In fact, compared with the mortality rate of civilian children, they have more medical security and live longer.
If you meet an extraordinary person in an extraordinary period, the prince and grandson may become victims of political struggle. For example, Qin Shihuang killed all his brothers and sisters, and there was an heir terminator like the Zhao Hede sisters in the Han Dynasty, who died abnormally and had no choice but to die young.