Tadaoki's second son was Okiaki HOSOKAWA who sided with the Toyotomi in 1615 during the Siege of Osaka and was subsequently and unavoidably ordered by his father to commit ritual suicide.
次男の細川興秋は、元和元年（1615年）の大坂の役で豊臣方に与したため、戦後に父の命を受けて自害を余儀なくされている。