Hatoyama is the son of Iichirō Hatoyama, who was Foreign Minister for a time. His mother, Yasuko Hatoyama, is a daughter of Shojiro Ishibashi, the founder of Bridgestone Corporation and heir to his significant inheritance. Yasuko Hatoyama is known as the "Godmother" within the Japanese political world for her financial contributions to both of her sons' political ambitions. In particular, Yasuko donated billions of yen when Kunio and Yukio co-created their previous Democratic Party of Japan (DPJ) in 1996 to help establish her sons' fledgling political party.