(Most historians believe that Sima Yue was behind the poisoning, but there is no conclusive evidence.) The recognized heir was Emperor Hui's brother, Sima Chi the crown prince, but Empress Yang, believing that she would not be honored as empress dowager if her brother-in-law inherited the throne, tried to have Sima Qin declared emperor; she was rebuffed by Sima Yue, however, and Crown Prince Chi succeeded to the throne as Emperor Huai. (Her attempt might have cost Prince Qin his life, as Sima Yue had him executed in 308.)