Question for hair experts?

Shaving/trimming hair makes it grow back more and thicker, correct? So wouldn't that apply to eyelashes? What's the alternative for removing hair WITHOUT making it thick( like pubes). For some reason I have hairy legs but short fine hairs on my arms. I've have non-hairy arms my ENTIRE life what the hell. Why is it I can't grow a beard or sideburns but pubes grow fast and thick?