Later on, however, a fight over the position of the head of the clan started with Koretoshi ASO and his son Koreie opposing Koretada ASO and his son Korenori.
しかし、やがて阿蘇氏は惟歳・阿蘇惟家父子と惟忠・阿蘇惟憲父子の間で当主の座を巡る争いが起こる。