It may help me, to do the mirroring. Not sure. I avoided Ancestry for awhile because I couldn't determine without a chromosome browser if our 2nd - 3rd cousins were a true 2nd cousin or endogamous match. Most are endogamous.

10 days ago I contacted my mother's other best match (FTDNA & 23andme) and went over her tree again and looked into her genealogy as I attempted to look for descendants in order to figure out who could've been my mother's parents. Then I asked this match if her great-grandmother had any siblings. She did, and once she revealed the names I remembered seeing it somewhere, and checked here with my closest match and I realized that it was through their ancestress I come from. Just had to figure out via which of the 4 children, 2 from one husband, 2 from another.

I also used 23andme's ethnicity portion on my mother's X to rule in if not rule out particular types of people who would've married into the family. And that was working, until last night I just tackled this closest match's closer relatives...the match here on Ancestry. And while looking for the females to look for descendants, I found a photo of one of them, and it looked like my mother and sister. Still trying to contact the descendants to see if that could be my mother's mother or aunt.