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In page Hōjō Masako:

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In 1180, Masako's elder brother Munetoki was killed at Battle of Ishibashiyama and Yoshitoki became heir of Hōjō clan.[citation needed] In 1181, Taira no Kiyomori died, leaving the Taira in the hands of his son Taira no Munemori. In 1182, Masako and Yoritomo had their first son, Minamoto no Yoriie.