Living here in eastern Mass, my two boys (24 and 25) grew up as Pats fans, knowing nothing but championships. I'd buy them Bills jerseys (McGahee, Dareus, etc) that they'd wear here and there, but with no real allegiance. A few years ago, about the time Josh became the starter, they started migrating over to the Light. Now, they're all in. My older one even had the pleasure of getting accosted by a drunk Pats fan at Foxborough this year while wearing my old Jim Kelly jersey.
We traded texts last night throughout the game, after which I said to them "Welcome to being a Bills fan. It's not for the faint-of-heart".