In contrast, Koxinga's father Zheng Zhilong left his Japanese wife not long after the birth of his son; Koxinga was a boy of seven when he finally joined his father on the Fujianese coast. It seems that Zheng Zhilong recognised his son’s talent and encouraged him in his studies and the pursuit of a career as a scholar-official, which would legitimise the power the Zheng family had acquired, using sometimes questionable means. Zheng Zhilong’s defection to the Qing must have seemed opportunistic and in stark contrast to Koxinga’s continued loyalty to the Ming. But it is difficult to deny that in refusing to submit to the Qing, Koxinga was risking the life of his father, and that the subsequent death of Zheng Zhilong could only be justified by claiming loyalty to the Ming. It has even been suggested that Koxinga’s fury at the incestuous relationship between his son, Zheng Jing, and a younger son’s wet nurse was due to the fact that strict Confucian morality had played such a crucial role in justifying his lack of filial behaviour.