Under the 'Find my iPhone' app, one of our phones listed now has a 2 beside it:
Listed like the above. What does that mean?
It means you have two devices using the same name. It has to do something to try separate them, so it adds a (2).
This can also happen if a single device is restored or set up as a new device, but is actually the same one. The initial device is preserved but a new one is set up to attempt to differentiate.