OK great, that is very helpful, thank you. And yes, I would set it up to have all these protected pages in a given directory.
A follow-up question:
This genealogy site would be outside of the wp infrastructure, i.e. without the wordpress templates, no header, footer, etc. Is this still possible, or would wordpress send a 404 error because these pages wouldn’t be part of any template?
Thanks again! Really appreciate your time.