It depends on if you are on the same server (if you all joined from the same time and in generally same locale, it is likely (but lucky) you are on the same server.)
If you have other friends than they who play, who are on the same server as you this can change what league you are in, also too I believe Q can be a determinant if their are enough on a server for that. This is my opinion from my own experience with RL and in-game friends.