Later, in 1045, when the Emperor Gosuzaku fell seriously ill, Yoshinobu pleaded with the Emperor Gosuzaku to will him as successor, and the Emperor Goreizei (elder brother from different mother of the Imperial Prince Takahito) decreed that the Imperial Prince Takahito be made the Crown Prince, so Yoshinobu was successful in his goal.
やがて1045年（寛徳2年）に後朱雀天皇が重態に陥ると、能信は天皇に懇願して、後を継ぐ後冷泉天皇（親王の異母兄）に対して「尊仁親王を皇太子にするように」という遺言を得るのである。