has anyone successfully located a long lost sibling?

I am 21 with 2 half brothers from my father. I’ve known one brother my whole life but found out about my other brother when I was about 15. My dad was never really in mine and my brothers life and has since passed away, and the mother of my other brother moved him away so he was literally never in his life at all. My grandma met him once when he was a baby and that was it. I believe he would be maybe 15 or 16 at this point. I know his name and where his mother moved him but I don’t know anything else. Since finding out about him i’ve always wanted to find him, just to see what he looks like. I don’t think I would contact him since I respect his mothers decision of keeping him away from my dad and family. I can’t ask my grandmother because she didn’t seem to like the fact that I knew about him since it’s kind of a hush hush thing. Any advice or tips on how I could potentially find him?