As you already discovered, the Nichodemus KEITH is the "other" KEITH family in the Titus County area. I don't really know too much about the origins of that family. However, like you, I have no doubt there is a relation.

I don't recall completely, but I don't think Nick and Alex were brothers. Instead, I think I recall them being from two entirely different families. Of course, that doesn't mean they weren't related farther back.

Keep me in the loop if you discover more.

Wes