So like, is Sebaru the First or Second Tsuchikage?

Yes, I do need to know this seemingly minor bit of logistics for Satsuma's background.

Long story short, his clan (ie parents, since he was like 3 at the time) started as a group of wandering martial artists (no, not ninja) but proved tough enough to be part of the founding clans of the village, so one could say they were among the first of the Iwagakure Ninja. Basically I'm trying to make sure this idea is even logistically possible.