I was told that May became very ill in the early to mid 40s - they were back in the Ladysmith area at the time. My understanding is that she died soon afterward. I believe they're connected to Hope Lutheran Church in Ladysmith. According to church records, Freida & Bessie were confirmed there on June 12, 1927.
I believe Chet & Freida are buried in Cornell, WI. I recall the long ride north to attend their 50th wedding anniversary in the late '70s.