hello! I have a logistical question. I currently have a T mobile account with my wife and I. My parents live in another state and want to join on. They want to port their numbers over from Att. How do we make this happen. -can they go to a T-Mobile store and join my account? -do I go to a T-Mobile store and do something? -a whole other option? Let me know what you think! Ideally they want to do this tomorrow to take advantage of Costcos BOGO galaxy 8 deal. Thanks!!