Okinaga married Tadaoki HOSOKAWA's daughter Koho, and adopted Tadaoki's sixth son as his adopted heir (Yoriyuki MATSUI); he was bestowed the new surname "Nagaoka" which was another family name of the Hosokawa clan, and called himself "Nagaoka Sado-no-kami."
興長は細川忠興の娘古保を妻とし、また忠興の六男を養嗣子に迎え（松井寄之）、細川別姓である長岡姓を賜り長岡佐渡守と称した。