Regarding Sr., Jr., III ... For most of history, "Sr/Jr" or equivalent did NOT have the current meaning of father/son. It was simply the notation which town clerks used in their records when there were two people, possibly unrelated, in town with the same name. When the older one died or moved, then the younger one would no longer need that notation. So those notations are relative and are NOT part of the name (except for the rare case when it is written into the birth certificate). On the other hand, "I", "II", "III" etc are typically used by the family to deliberately mark a lineage, although they may or may not indicate direct father/son connections. Furthermore, they are sometimes applied carelessly or in competition with another branch of the family. So, in both cases, don't get hung up on differences in the suffixes that appear in records.