The Sue Barton series, seven novels about an irrepressible nurse, is set approximately in the 1940s. It follows the eponymous Sue from nursing school (based on the author's experience at Mass General) to wife to a busy doctor and mother of three children. The author, Helen Dore Boylston, was a real person (in contrast to the famous Stratemeyer Syndicate - not that I didn't enjoy those books as well) and friendly with Rose Wilder Lane, the daughter (as you know) of Laura Ingalls Wilder.
I read and reread the reprints of the original Little, Brown editions at my local library (and of her other series, the Carol Page books, but they were less memorable) but when it came time to own copies of my own they were very scarce. I found Sue Barton, Senior Nurse at a NYPL sale but the other books pictured came from Australia. Sue Barton, Neighborhood Nurse looks much too religious - part of Sue's appeal was that she was outgoing, accident prone, and fiercely loyal (not just to her friends but to the programs where she received her nursing education). I never had any intention of going to nursing school but loved reading about her experiences, and was very disappointed the first time I met a real nurse that she did not wear a cap like Sue. Image Cascade has brought the books back into print with charming covers but I think my mismatched set will have to do.