Dear John,
My knowledge of Mises, such as it is, is largely confined to his theoretical works: Human Action, Socialism, Liberalism, Theory and History etc. I know little beyond the merest outlines of his personal life. The place to find the answer to your question is, I suspect, Professor Hulsmann’s Mises: The Last Knight of Liberalism, available at https://mises.org/library/mises-last-knight-liberalism-0.
I hope that you can find the answer to your question there.
Best wishes,
Gerard Casey
