Thank you for posting your question on History Hub.
The National Archives and Records Administration (NARA) does not provide services to locate living individuals. The records in the custody of NARA were typically transferred from other Federal agencies at least 20-30 years after they were created and used. Therefore, NARA records are not usually helpful in providing current information about individuals.
The Social Security Administration (SSA) may be able to help locate living persons in the following manner: A letter to the missing person placed in a stamped, unaddressed, and unsealed envelope may be sent to either agency along with an explanatory cover letter. The agency will examine the letter and decide whether to forward it to the person.
The SSA has addresses for individuals who have received benefits in the past two years. In your cover letter, provide as much of the following information as possible: name, social security number, date and place of birth, mother's maiden name, and father's name. Address your communication to:
Social Security Administration
Letter Forwarding unit
6401 Security Boulevard
Baltimore, MD 21235
If you are seeking more information about the daughters and their names, genealogical research may help. Although only 1-3% of the records created by the Federal Government are transferred to the National Archives, our holdings consist of hundreds of thousands of records, many of which may be of genealogical value. The vast majority of our records are not name-searchable. You will need to begin your research by determining the agency with which your subject interacted and exactly what types of records you wish to see.
For more information on conducting genealogical research within our records, please visit our webpage: https://www.archives.gov/research/genealogy.
We hope this information is helpful in your research.
National Archives and Records Administration