I saw a barefoot Joan open the show for Bob Gibson at the Gate Of Horn folk club in Chicago in 1959 I think. Of course, the voice blew me away.But it was her sister, Mimi, that I fell for in the early 70s when I opened a show for her at the club on the Northwestern University campus called Amazing Grace.
My thoughts are with Mimi right now---as are Joan's--I'm sure...
Art Thieme