Why does it involve the thirteenth brother of Emperor Kangxi? What about the result of implicating him twice?

Old three and old four are best friends. His old four participated in the abolition of the prince twice, but he pretended to be a sincere psychological Buddha and did not participate in the struggle to confuse his old man's house and gain good feelings. The third is to protect the fourth, so he didn't say anything, and everything was resisted by himself. As a result, he was circled, and he became a prisoner from Kangxi's favorite prince. Not only did he lose the opportunity to inherit the throne, but even the prince and Beizi did not have his share. If Kangxi hadn't died, his fourth brother would have been locked up for life. The advantage is that he has won all the trust of Yongzheng, a tyrant, and has the power to pour the world! Under one person, thousands of people only went to bed, and it was for the benefit of future generations. Later, his son took part in the rebellion, but Qianlong took care of his feelings and simply cut his title!