In 1587, Masayasu SOGO met a heroic end in the battle of Hetsugigawa, leaving word to his vassal 'Senmatsumaru has not had an audience with Hideyoshi TOYOTOMI yet. Be sure to have him have an audience with Hideyoshi after my death, to succeed me and carry on the name of the SOGO family.'
天正14年（1587年）、戸次川の戦いに参戦していた父の存保は「まだ千松丸は豊臣秀吉に謁見してない。自分が亡くなったら必ず秀吉に謁見させ、十河家を存続させるように」と家臣に伝えて、壮絶な戦死を遂げた。