Whose son is Zhang Wuji?

I want to ask "whose son is Zhang Wuji in the novel Eternal Dragon Slayer"? He is the son of Zhang Cuishan and Yin Susu.

Zhang Wuji, alias Zeng, the hero of Jin Yong's martial arts novel The Dragon Slayer, was born in 1337 (Yuan Dynasty). He is handsome and heroic, and he is one of the best figures in Jin Yong's novels. Zhang Wuji, one of the seven chivalrous men in Wudang, is the Wu Tangmen in Wudang, the son of Yin Susu, the main owner of Wei Zitang, the hawk of heaven, the adopted son of Xie Xun, the golden lion king of Zoroastrianism, and the 34th generation leader of Zoroastrianism in Middle-earth.