On the other hand, another historian, Yosuke WATANABE, asserted that Soun originated from the Kyoto-Ise clan, was a steward for the Bakufu government as stated in the "Kansei Choshushokafu," and that Soun was either the same person as Sadafuji ISE, Sadachika ISE's younger brother, or his son.
これに対して渡辺世祐は『寛政重修諸家譜』などにある幕府政所執事の京都伊勢氏の出身で、伊勢貞親の弟伊勢貞藤またはその子供であろうとする京都説を主張した。