The Japanese royal family inherited the tradition.

When I first saw the news, I thought that the current emperor had no children, so I made my brother the next emperor. However, after careful review of the information, it is found that the current emperor has a son. His son is second in line to the throne. Combined with the tradition of learning Confucian culture in Japan, it is likely that the thought of brotherhood has played a leading role. In fact, in the history of our country, many dynasties were passed down from the eldest brother to the younger brother when he was emperor. However, the royal relationship in feudal China was not chaotic, while the Japanese royal family was quite chaotic.

The Japanese royal family is a big family where close relatives get married. Even brother and sister love each other, which is a tradition. It is understandable to say that brother and sister love each other. After all, this is a tradition left over from feudal times. Then, what happened between Emperor Heisei and Fujiwara was a great surprise. Fujiwara Yeh is the favorite disciple of Emperor Hirai, but Fujiwara Yeh's daughter married Emperor Hirai. In the end, Heisei chose to live with her mother-in-law and daughter-in-law.

The Japanese official explanation is that the Japanese emperor is a descendant of the gods, so in order to ensure the purity of the blood of the gods, the Japanese royal family can only be combined with its own people. In this way, although the bloodline is pure, the marriage of close relatives is a headache for the Japanese royal family. Because consanguineous marriage can cause many genetic diseases. This question has been made clear in high school biology. Even if there is no genetic disease, offspring will break out from time to time.

I read an article on the internet before, saying that the Japanese royal family has a short life span and has no longevity. Whether it is really necessary to study, because the life span of ancient people is very short. But there seems to be no problem as a witness. I think it is very likely that the influence of consanguineous marriage has been basically eliminated with the flourishing of the royal family. However, the kinship between Japanese royal families is still very chaotic. Cousins marry cousins from time to time.