The Second Prince was not helping the Crown Prince to rebel. It was the Eldest Princess who urged the Crown Prince and the Second Prince to rebel together. In order to protect the Eldest Princess, the Crown Prince believed that he still had a chance to make a comeback after being deposed. If he succeeded in his rebellion, he would gain even more. The Second Prince realized that he was a whetstone given to the Crown Prince by the Qing Emperor. His fate would be very miserable. The only chance of survival was for the Crown Prince to step down and take the throne himself. At the same time, he was also urged by the Eldest Princess. These factors pushed him onto the path of rebellion.

The reason why the Crown Prince and the Second Prince rebelled was their sense of threat to Fan Xian and their motive to fight for the throne. The Second Prince believed that Fan Xian was the son of the Qing Emperor and Ye Qingmei, and that he had the highest chance of ascending the throne. Both the Crown Prince and the Second Prince wanted to protect their own interests and power, so they took the action of rebellion.
The reason why the Crown Prince and the Second Prince rebelled was their sense of threat to Fan Xian and their motive to fight for the throne. The Second Prince believed that Fan Xian was the son of the Qing Emperor and Ye Qingmei, and that he had the highest chance of ascending the throne. Both the Crown Prince and the Second Prince wanted to protect their own interests and power, so they took the action of rebellion.
The reason why the Crown Prince and the Second Prince rebelled was their sense of threat to Fan Xian and their motive to fight for the throne. The Second Prince believed that Fan Xian was the son of the Qing Emperor and Ye Qingmei, and that he had the highest chance of ascending the throne. Both the Crown Prince and the Second Prince wanted to protect their own interests and power, so they took the action of rebellion. In the end, their rebellion plan failed. The Crown Prince committed suicide, and the Second Prince committed suicide after being suppressed by Fan Xian. This information could answer the question of why the Crown Prince and the Second Prince of Joy of Life rebelled.
The reason why the Crown Prince and the Second Prince rebelled was their struggle for the throne and their sense of threat to Fan Xian. The Crown Prince's goal of slandering the Second Prince was to stop Fan Xian from taking away the power of the palace treasury and to give the Qing Emperor a reason to start a war against Northern Qi. The Crown Prince understood the Qing Emperor's thoughts and knew that the Qing Emperor needed a reason to start a war. Thus, he used the lack of evidence to slander the Second Prince to satisfy the Qing Emperor's needs. The Second Prince believed that Fan Xian was the son of the Qing Emperor and Ye Qingmei and was likely to become the person most likely to ascend the throne. In order to seize the throne, he raised an army to rebel. In the end, the Second Prince's rebellion failed and he was imprisoned. The Qing Emperor's attitude toward the Second Prince was harsh. In the end, the Second Prince chose to commit suicide.
The reason why Crown Prince Qing Yuannian rebelled was his sense of threat to Fan Xian and his desire to fight for the throne. The Crown Prince believed that Fan Xian was the son of the Qing Emperor and Ye Qingmei, and that he had the highest chance of ascending the throne. Therefore, in order to protect his own interests and power, the Crown Prince took the action of rebellion. However, the specific details and background information were not mentioned in the search results provided.
The reason why Li Chengqian rebelled was because he was worried that he would lose his position as Crown Prince. During the reign of Emperor Taizong of the Tang Dynasty, the competition for the position of Crown Prince was extremely intense. Li Chengqian felt that his position was threatened. His younger brother, Li Tai, gradually gained a group of supporters. This made Li Chengqian feel uneasy about his position as Crown Prince. In addition, the relationship between Li Chengqian and Li Shiming gradually deteriorated. Li Shiming was very strict with his discipline and even ordered the execution of one of Li Chengqian's favorite Tai Chang Le people. The struggle for power between the brothers was also one of the reasons for Li Chengqian's rebellion. Although he was the Crown Prince, his talent was far inferior to his younger brother, Li Tai. On the whole, Li Chengqian's rebellion was due to his fear of losing his position as Crown Prince, and it was related to the conflict between his brothers and his father.
Crown Prince and Crown Prince were two different titles. According to the documents of Noble Prisoner and Nanjing Daily, Zhu Biao was the son of Zhu Yuanzhang and was made the heir and crown prince. And according to the documents of Great Ming Elegance, the conversation between the Crown Prince and the Crown Princess showed that they were a couple and had a son. According to the document " The Hat of a Prince of the Ming Dynasty "," A Study of the Apparels Unearthed from the Tomb of the King Huang of the Ming Dynasty ", the royal family members below the emperor of the Ming Dynasty, such as the crown prince, the prince, and the prince, had some differences in their clothing. In summary, the crown prince and the shizi were different titles. The crown prince referred to the emperor's son, while the shizi referred to the emperor's eldest son.
There were different opinions on whether the Third Prince was the Crown Prince or not. Some documents stated that the Third Prince of the Qing Dynasty was the Crown Prince, while others believed that the Crown Prince and the Third Prince were different people. According to the relevant documents, the Crown Prince was the Qing Emperor's eldest son, and the Third Prince was the Qing Emperor's fourth son. Although the Qing Emperor initially wanted to support the Crown Prince as the successor, he eventually abolished the Crown Prince and placed the Eldest Princess under house arrest. In the plot, the Third Prince became the Emperor of the Qing Kingdom. Therefore, according to the information provided, the Third Prince of the Qing Dynasty was not the Crown Prince.
There were many reasons for Li Chengqian's rebellion. First, he felt that his position was threatened. His younger brother, Li Tai, was conferred the title of King of Wei and gradually gained a group of supporters. This made Li Chengqian feel uneasy about his position as Crown Prince. Secondly, Li Chengqian's expectations of Li Shiming were too high. He felt that the gap between his treatment and his younger brothers was too big, which made him feel dissatisfied. In addition, Li Chengqian was also strictly controlled by Li Shiming. He had a good impression of a person who was good at singing and dancing, but Li Shiming ordered the execution of this person, which intensified the conflict between father and son. Combining these reasons, Li Chengqian decided to rebel.
There were many reasons for Li Chengqian's rebellion. First, he was afraid that he would not be able to become the emperor because he felt that his position was threatened, especially when his younger brother, Li Tai, was conferred the title of King of Wei, which gradually gained a group of supporters. Secondly, Li Chengqian was dissatisfied with Li Shiming's discipline. He did not want to accept Li Shiming's arrangement of finding a tutor for him. In addition, Li Chengqian was angry that Li Shimin had dethroned him from the throne. He felt that he had been deprived of his right to inherit the throne. Finally, there was another theory that Li Chengqian was in love with a person from Tai Chang Le, causing dissatisfaction and conflict. In general, there were many reasons for Li Chengqian's rebellion, including status threats, dissatisfaction with discipline, dethronement of inheritance rights, and personal feelings.