The succession to the throne in China is generally the succession of fathers to sons.

If the emperor has no sons, he can make a younger brother (or the son of a brother). There is also a situation in which the emperor dies later than his own heir (the crown prince), and before the emperor dies, the son of the crown prince, that is, his grandson, is the crown prince, which is a special group of people in the Chinese imperial hierarchy - the emperor's grandson.
The number of emperors and grandchildren is not much, counting the young ones, who did not become emperors in the end, added up, there are only 11 people in total. However, it is also necessary to subtract the fact that his father is still alive and become the emperor's grandson, which refers to only six people who were made the emperor's grandson by their grandfather after the death of their father. However, if Sun Tzu becomes emperor directly, the end is not very good.
The earliest emperor to be succeeded as emperor by the emperor's grandson was Xiao Zhaoye, the king of Yulin in Southern Qi (only after the Qin Dynasty).
In 479, Xiao Daocheng, the King of Qi, deposed Emperor Shun of Song and established the Qi Dynasty, known in history as Southern Qi.
The Greatest Characteristic of the Emperor of Southern Qi was that he gave birth to a son very early. Xiao Daocheng grew a 13-year-old son Xiao Zhao, Xiao Zhao grew a 18-year-old son Xiao Changmao, and Xiao Changmao grew a 15-year-old son Xiao Zhaoye. Xiao Daocheng died after four years on the throne, and the 44-year-old Xiao Zhao succeeded to the throne as Emperor Qiwu. Xiao Zhao died after 11 years on the throne, because crown prince Xiao Changmao died not long ago, and Xiao Zhao had to appoint The Emperor's eldest grandson Xiao Changmao as the emperor's grandson. Soon, Xiao Zhao died and Xiao Zhaoye succeeded to the throne. Xiao Zhaoye was very absurd and funny, he was emperor for less than a year, and he also tossed the country for a year, and chaotic things appeared endlessly, and chicken feathers flew everywhere. Xiao Daocheng's nephew Xiao Luan seized the opportunity to control the imperial government, and then planned a murder, killing his nephew Xiao Zhaoye in the midst of the chaos and establishing himself as emperor.
The next emperor's grandson to become emperor was in the north six hundred years later, that is, the Khitan Liao Dynasty. In the Eight Parts of the Heavenly Dragon, Yelü Hongji, who worships Xiao Feng, is also known as the Liao Daozong.
This duke was a late monarch, and the Liao Dynasty was already in decline under his rule. Yelü Hongji forced his son Yelü Jun to die, and regretted it again, and made Yelü Yanxi, the son of Yelü Jun, the emperor's grandson. After Yerushalayim succeeded to the throne, the index of fainting was several times better than that of his grandfather. Obsessed with fun, the government rotted, and demanded from various ministries excessively, and finally forced the Jurchen leader to finish Yan A bone beating. Ah Kuan rebelled, and finally in 1125 the Liao was destroyed, and Yelü Yanxi was captured. As for the method of death, some say that they died of illness, some say that they were shot by ten thousand arrows, and the time of death is also disputed. But in any case, Jeroboam's life was a failure. Jeroboam had a son, but his son did not survive.
Next came the Jin Dynasty, where two emperors were emperors. The first is Kim Hee-jong's completion of Yan Qi, the situation is slightly special.
He was the grandson of the founding father-in-law Ah Kuan Da, who died and was succeeded by his brother Wu Begmai, who destroyed the Liao and Song dynasties, and became known as Jin Taizong. Wu Begmai had many sons, but he knew that Jiangshan was made by his brother Ah Bone, so he did not pass it on to his son, but set up Ah Bone's eldest grandson Hela (亶). At that time, when the Jin Dynasty was first established, the system was not complete, and it was not called the Emperor's grandson, but called The Great Strength of the Ban Bo, which was the meaning of the successor. After Jin Xizong succeeded to the throne in 1135, he returned to the Qing Dynasty for the sake of government, and promoted the process of Sinicization of Jurchens. But later, he was addicted to alcohol and killed indiscriminately, and his cousin Quan Yanliang took the opportunity to kill him in 1150. Two of Yan Qian's sons also died early.
Yan Liang did not have a good ending. Eventually, when he attacked the Song Dynasty from the south, he was killed by The Completed Yan Yong, who was also the grandson of Jin Taizu, and Finished Yan Yong succeeded to the throne in Liaoyang, Tokyo, that is, Jin Shizong.
After Yan Yong reigned for 29 years, the Jin Dynasty reached its peak, and the Southern Song Dynasty bowed to Jin. In the second year of Dading, Yan Yong made his second son, Yan Yungong, the crown prince, and Yan Yungong had a good quality, and he was a material for a Ming Jun, but he was not blessed. Died in the twenty-fifth year of Da Ding, only 40 years old. Subsequently, the elderly Yan Yongli Yungong's concubine Completed Yan Ma Da Ge was made the emperor's grandson, and the Chinese name was Completed Yan Jing. In the first month of the twenty-ninth year of Dading (1189), he succeeded the emperor as emperor.
After Yan Jing's reign of 18 years, the Jin Dynasty continued to move forward in the prosperous world, known in history as the rule of Ming Chang, but the crisis of the prosperous world has emerged. In the early stage, it was OK, but in the later stage, Yan Jing began to eat and drink, the state affairs were weakened, and the foreign enemies gradually grew. Later, the Mongol-Ancient Empire that swept through most of the world, Ironwood really continued to grow, starting from the era of Yan Jing. It's just that the foundation laid by the ancestors for Yan Jing was too solid. In the next 18 years, the Jin Dynasty would not be as badly beaten by Temujin as it was later. After Yan Jing's death, the Jin Dynasty was completely unavoidable.
Fortunately, Yan Jing's own fate was not bad, and he died well, but the heir was very sad. Emperor Zhangzong had six sons, all of whom died before Emperor Zhangzong, and Emperor Zhangzong had no queen, so Emperor Li's uncle Yan Shouji was made a king.
When Kublai Khan destroyed the Southern Song Dynasty in 1276, he was already a 61-year-old man. Regarding the inheritance of the throne (Khan's throne), Kublai Khan had already made arrangements. As early as 1261, when Kublai Khan established the state as yuan, he made his concubine Zhenjin the King of Yan and crown prince in 1273. As long as the old father dies, Zhenjin will be the Emperor of the Great Yuan. Unfortunately, he did not consume a long life of his father, and in 1285, at the age of 42, Zhenjin died of illness. Kublai Khan lived another 9 years until his death in 1294. In 1293, when he was dying, Li Zhenjin's third son Timur was made crown prince. Timur succeeded to the throne, that is, Yuan Chengzong.
Yuan Chengzong was not a Ming Jun, nor was he too dimwitted, but he was confused and spent 14 years as an emperor. Timur was the Emperor of Neizhi, and he no longer killed everywhere like his grandfather, paying attention to the reconciliation of interests of all classes within. In the end, there was no major outbreak of contradictions in the country. However, at the beginning of the Great Virtue, Timur sent troops to attack the eight hundred daughters-in-law country located at the junction of Thailand and Burma, and the descendants were almost confused by this country name, and the chicken feathers in this battle flew randomly and did not catch anything. Timur did a very important thing, that is, to posthumously honor Confucius as the Most Holy Wenxuan King of Dacheng and widely honor Confucius. Timur had a crown prince named Deokshou, but he hung up in the ninth year of Dadeok (1305), and two years later, Timur also hung up. Later, his empress Dowager Buluhan was not content to be lonely in politics and rule, and competed with Chengzong's nephew Haishan brothers (i.e., Emperor Yuanwuzong and Yuanrenzong), and in the end, Emperor Renzong (whose name was too long) won, but ceded the throne to Haishan.
The last crown prince, everyone is familiar with, is the Jianwen Emperor Zhu Yunjiao, who does not know the end now.
However, the only thing that is certain is that Zhu Yunjiao is definitely dead. His grandfather Zhu Yuanzhang spelled out the great tomorrow with an extremely poor world, and the world knows about Zhu Yuanzhang's temperament. However, Zhu Taizu was particularly fond of the meek eldest son Zhu Biao, and hoped that Zhu Biao would be able to smooth out in the future, and he was made crown prince as early as the establishment of the Ming Dynasty. Even in order for Zhu Biao to get a power battle without thorns, Zhu Yuanzhang went on a killing spree, and the blood flowed into a river. Zhu Yuanzhang's sons, the most similar to Zhu Yuanzhang is the old fourth Zhu Di, but Zhu Di does not dare to have any ideas about the eldest brother Zhu Biao. Unfortunately, Zhu Biao also did not have an imperial order, and in 1392, Hongwu died in the twenty-fifth year.
After Zhu Biao's death, Zhu Yuanzhang actually considered making Zhu Di the crown prince, and whether Liu Sanwu's affairs were true or false, no one could say.
However, the more popular saying is that Zhu Yuanzhang did not consider Zhu Di and other sons at all, and directly fell in love with the emperor's grandson Zhu Yunjiao, because Yunjiao was too similar to his father Zhu Biao.
Later events were all too familiar, and in 1399, the Hongwu Emperor died and was succeeded by the crown prince Zhu Yunjiao. Originally, Jianwen could still stabilize Jiangshan, but it was too gentle, and there were too many pig teammates around him, Zhu Di almost admitted it, and was actually smashed by Zhu Yunjiao himself. In the end, the Yan army entered Jinling, and in the sky-high flames, Zhu Yunjiao did not know where to go, which has become one of the most worrying mysteries in history. It is said that it may have crossed the ocean to France, and Mr. Juberi said that his ancestors came from some overthrown emperor in China...
After that, there was no longer a grandson of the Emperor.