I run 3 mages in my 5 box trinity team and they are the "morgana sisters". When my wife started playing the game she rolled a rogue and managed to level her character very fast (she plays every day, I play only on the weekends). So sometimes I will sub her in on instance runs to get her geared up, and I always pick the same "sister" to leave out. She was even at one point 2 levels behind her sisters and I had to play her solo to keep up. It's fun though, I have taken pictures of the team's journey and have even started a little side story of the drama the poor sister had to go through being left behind.

It is amazing how much fun and life MB brings to WoW. You really feel that you have a team/family/army at your disposal and each has their own personalities