I bought an iPhone 6 directly from ATT.com with Next using another family members line. The other family members line is an iPhone 4s which uses a micro sim card which I want to keep active. I understand that if I were to turn on the new phone 6 on, it would automatically activate the sim inside of it and deactivate the micro sim card in the iPhone 4s. If I were to stick my own ATT activated iPhone 5s nano sim into the iPhone 6 and turn it on for first time, would it work? I will then throw away the nano sim that came with the iPhone 6. Would this keep the micro sim in the iPhone 4s still working? If this is a retarded question, flame away.