In 1664, Kagekatsu's grandson, Tsunakatsu UESUGI, died suddenly and there was a danger of the family dying out, but due to efforts by Tsunakatsu's father-in-law, Masayuki HOSOKAWA, who was a younger brother of Iemitsu TOKUGAWA, Tsunanori UESUGI, the son of his daughter's husband, Yoshihira KIRA (Kozu no suke, descendant of the female side of Ogigayatsu Uesugi family) became an adopted son of Tsunakatsu, and as a result the family was permitted to continue its family name with a half stipend of 150,000 koku (30,000 koku in actuality).
1664年、景勝の孫上杉綱勝が急死して断絶の危機を迎えたが、綱勝の舅保科正之（徳川家光の実弟）の尽力により、妹婿吉良義央（上野介、扇谷上杉家の女系子孫）の子上杉綱憲が綱勝の養子に入りした結果、半知15万石（実高30万石余）で家名存続することを許された。