I really like a boy but he's my best friends brother and its really awkward because he likes me too, what do I do?

Are you worried about damaging your relationship with your friend should things with her brother go south? If so, then weigh your options. If you really feel compelled to act on the feelings you have for this boy, then do it. However, know that she may take his side if/when you two break up and you may lose a friend. You seem very, very young and infatuations are frequent and short in youth. I wouldn't be inclined to risk a great friendship over a crush when I'll likely have a different crush next week. Good luck.