When do guys stare at girls?

When people stare at something or at someone its always because they are probably just admiring you or they could just be thinking about something else

but since you claim that he stares at you all the time is because he's probably thinking of building up courage to talk to you, but it seems this guy is really intimidating by you.

The other thing is that he probably doesn't want to talk to you because he knows you like him and he doesn't want you to like to much so that if you guys do end up growing something your cousin won't feel unconformable.

what your to do is try to talk to him, break the ice, ask him why he doesn't talk o you but don't do it to straight forward.