Savato said
Because Naruto totally knew Nagato beforehand. Yet they descend from the same clan. I guess it depends on the backstory? Because ya' know, if the clan is divided or some have been on their own for a long time, would make sense that they're strangers to clansmen who never met them before they've left.
... Naruto and Nagato were from two different villages. That example is completely invalid for this case. Naruto didn't even know who his parents were until he reached a certain age.
I'm talking about in Konoha. -.-