O-Ie Sōdō
In his final years, Tadakatsu instigated an "O-Ie Sōdō" by attempting to disinherit his own son, Sakai Tadamasa, in favor of his younger brother, Sakai Tadashige in 1642. This action was greatly opposed by the domain's senior advisors and "karō" and Tadakatsu died in 1647 before the issue was resolved. The ō Matsudaira Nobutsuna ruled in favor of Sakai Tadamasa as successor.