As for the question who was the real father of Hideyori, well-known opinions have named Harunaga ONO and Mitsunari ISHIDA (also Katsumoto KATAGIRI), and a ridiculous view named Ieyasu TOKUGAWA and Sanzaburo NAGOYA.
では秀頼の実父は誰かという問いに対しては大野治長説と石田三成説が有名で（片桐且元とも）、珍説の類では徳川家康説、名古屋山三郎説がある。