According to the 1940 census all children of Shinsho were born in Hawaii.
If you're looking for the mother of the 1st three daughters, since they were all born before 1930, I suggest doing a Genealogical Vital Record (Birth Record) request of your Auntie from the State of Hawaii Health Dept.
Any private individual or individual employed, endorsed, or sponsored by a governmental or private organization or agency, working on genealogy projects may apply for issuance of copies of vital records on file with the Department of Health. Any applicant seeking issuance of copies of vital records of events that occurred seventy-five years or less prior to the current year must establish a direct and tangible interest in the records to be eligible for them (see Certified Copies for more information). An applicant need not establish a direct and tangible interest in vital records of events that occurred more than seventy-five years prior to the current year to apply for these records.
Applications for issuance of copies of vital records by an individual working on genealogy projects must be submitted in writing. No telephone or Internet (e-mail) requests will be accepted. Send applications by postal mail to:
State Department of Health Office of Health Status Monitoring Issuance/Vital Statistics Section P.O. Box 3378 Honolulu, HI 96801
The application should include the following information:
the name of the applicant, if appropriate, the organization or agency employing, endorsing, or sponsoring the applicant,
a brief description of the genealogical project the applicant is working on,
a list of names of individuals whose records the applicant desires to obtain,
and the type of record (birth, death, marriage, or divorce certificate) or records for each of the named individual that the applicant desires to obtain.
For vital records of events that occurred seventy-five years or less prior to the current year, the applicant must establish a direct and tangible interest in the records.
For issuance of copies of vital records, the applicant will be charged the same fees as for certified copies ($10.00).
Genealogy requests are not considered urgent and are not processed as priority requests.
This is your best avenue for the information you seek. Unfortunately, it may take up to 4-6 months to process and may not arrive in time if your Auntie is dying, but at least the mystery would have solved. You might try submitting with your request a plea (last dying wish scenario) to see if they might expedite the process. Good luck, Ryan.