In the capital, Sima Jiong became arrogant based on his accomplishments. He had his sons created princes, and ran the matters of the central government from his mansion, rarely visiting the emperor or attending the imperial meetings. He enlarged his mansion to be as large as the palace, and he entrusted matters to people who were close to him, and would not change his ways even when some of his more honest associates tried to change his behavior. When Emperor Hui's grandsons Sima Zang and Sima Shang (), successive crown princes, died in childhood, leaving Emperor Hui without male descendants by 302, Sima Ying was considered the appropriate successor, but Sima Jiong chose to bypass him by recommending the seven-year-old Sima Qin () the Prince of Qinghe (Emperor Hui's nephew and the son of his brother Sima Xia ()) as the crown prince, with intent to easily control the young Crown Prince Qin.