However, according to the historical records kept by the Nanbu clan, by 1338 the signatory of Ikkenjo (acknowledgement of reading military document) was made by his elder brother Morosue and no historical records of Iesue were to be found thereafter.
しかし、南部氏に伝わる史料によると、1338年（建武4年/延元2年）には、一見状の発給元が兄師季に代わっており、これ以降家季に関する史料は見えない。