Wait, does his cousin like him?

Same question, but rn im so lost is he is his or his friend-

Same question, but rn im so lost is he his cousin or his friend-**

Wait...were they cousins?
I thought this was chinese and in China(well, most asian countries), if you are close to a person, or are good friends, sometimes you refer to them as family members like cousin, brother, or sister. If I'm wrong, then nevermind, but that's what I do even if I'm not related to them(well, only to my chinese friends I had before).
Example: In korea, hyung means older brother or used for a male to address another male older than himself. Or ahjussi in Korea, used to address a middle aged man yet also translates to uncle.
I don't know why I'm using korean examples when I'm chinese, I just felt korean examples were easier to understand -_-

I forgot to say that (I think) most of this was established in "ancient times" where they still had deciples because calling someone "eldest brother", "second brother", "fourth [younger] brother" and so forth was a sign of intimacy and showed closeness. So I think the brother/sister/cousin that people say has still carried on today. That's why I'm not sure how to tell if people in china are actually related unless it's by their surname and generational name.