However, he sent Tadahide back to his birthplace and requested the bakufu (Japanese feudal government headed by a shogun) to designate his illegitimate son Sentaro (who later became Tadaaki) as his legitimate heir and his third son Yojuro (who later became Tadachika) as Sentaro's adopted son, which was finally approved in 1667.
だが、この忠栄を生家へ還し、寛文7年（1667年）庶子の千太郎（長じて忠昭）を嗣子、順養子を三男・与十郎（のちの忠周）という幕府への願い出に対し、ようやく認可が下りた。