Unfortunately it does not list her parents and they don't have a death certificate for her for some reason. Her obituary may be helpful if for no reason as it may list siblings. However, it lists her as a widow as does the census. Are you sure James left for Nebraska? The James B. Myer who married Hallie and lived in Nebraska was a younger man.
It lists her parents as Thos J. Cain Jr and Nancy.
The death certificates for their children might be helpful. In the database above it would include S. C. Cain 1931, Daniel Cain 1955, Mary Mickleson 1920, Martha Eaton 1957. Nancy's maiden name was Enoch.