OK, serious question.

I am researching a mansion in southern NJ (1826). Existing 6-panel doors seem
consistent with an early period of construction. There is one with fixed
louvers, mounted on the door frame between the 1st floor main (central) hall
and the adjoining stairhall. It is reported (1957) that there were other
doors with fixed louvers elsewhere in the house. No evidence of those doors
exists today. (It went through a "restoration" in the early 70s -- we are
trying to trace what's left of original fabric.) I have seen other examples
where bedrooms had 2 doors-- one solid with panels on outside of door frame,
the other a fixed-louver door mounted on the inside, swinging into the room.

Q: Anyone know period of significance for interior doors with louvers? More
often fixed or moveable? Always (usually?) paired with a solid door? Are they
primarily southern in origin (the early owners had some connections in
Charleston)? How prevalent were they in the Middle Atlantic states?

Any helpful push in the right direction would be great.

Mary Krugman