Okay. I need boyfriend help.?

He is four almost five years older than me. I like him and all but im not sure if we should date. We were like really close and I dont like want anything to happen and we to like not even talk anymore. Like i dont want to lose that brotherly figure because i dont exactly have one. We both want to take it a step further but i dont know if my mom will let me. She knows him and all so that part is okay. But the one problem is I dont even know if she would let me date anyone. Not just him. And I know that he does love me because he isnt the type of person that lies. We are already going out and stuff. But how can i tell her. Also, can you give me any tips or advice? If you can that would be great.