I updated my iPod from 5 - 6 today and so did a co-worker on her iPhone. But I was trying to update my boss' iPhone to iOS 6 and the "Software Update" wasn't there between About and Usage. I found out that she's currently running OS 4.3.5 on her iPhone 4. How do I go about upgrading that to iOS 6? Do we have to update it to iOS 5 first? if so, how do we do that?