memoir: some fine details to the parts about "Helen" and Sophia

Writing is impossible! (Even little parts of the story that don't
"really matter" have all sorts of little details to them—I added a
point to the far editing tier where I still don't think I got this
right—and I want to explain the details correctly because I think it's
a cute window onto the tapestry of my life, but if I spend too long on
every detail, then I'm not going to finish telling the Whole Dumb
Story before the world ends)