Hey folks, quick question. I'm "stealing" my daugher's phone upgrade since she just got a new phone herself. When the phone comes, do I have to activate it on her line, then somehow switch it to mine or can I just activate to my line? And how does the 4G work, do I just use the old 4G LTE card I have in my current phone with the new one? We have the unlimited/share everything plan. Thanks!