Because cousins are cousins, my aunt's daughter is still a little far away. In the eyes of the ancients, the blood relationship is far away. Cousin is my uncle's daughter (both my father's brother), and the ancients thought that blood relationship was close (men are superior to women! )。 In short, the same surname is Tang and the opposite sex is Table.
This can be traced in many novels. For example, in A Dream of Red Mansions, Baoyu's sisters Lin and Bao are cousins, but not in Yingchun and Tanchun. The Qin that Chueh-min can marry at home is also a cousin, but if Shuhua (that is, his cousin) is changed, he can't marry ~
I hope I can help you!