I'm running ios 6.0.1. Tonight I was trying to hold a group MMS messaging with my 2 sisters. 1 sister has an iPhone and 1 sister has a Galaxy. Sister with the iPhone started the text and I could see her replies. Then the sister with the Galaxy chimed in and I could no longer see any replies. The sister with the Galaxy started showing up in another thread. The sister with the iPhone completely disappeared from the thread iMessage, Sends as SMS, MMS Messaging and Group Messaging are all turned on but it's not working at all. I had an iPhone 4 prior to this and had no problems with Group MMS. Any ideas about what to do??