Dear Taylor Scott,
Thank you for posting your request on History Hub!
If you have not already consulted the records of the Federal census, we searched the National Archives Catalog and located the Population Schedules for the 1850 Census, the Population Schedules for the 1860 Census, the Population Schedules for the 1870 Census, the Population Schedules for the 1880 Census, and the Population Schedules for the 1890 Census in the Records of the Bureau of the Census (Record Group 29) that may contain information about Isabelle Saint, Robert Harvey Jeans, and their parents in Alabama. For more information about the non-digitized schedules, please contact the National Archives at Washington, DC - Textual Reference (RDT1) via email at firstname.lastname@example.org.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT1. We apologize for this inconvenience and appreciate your understanding and patience.
You may wish to search Ancestry or FamilySearch for the U.S. Census. There may be a fee for using Ancestry. Instead, please check for access at your local library as many library systems subscribe to these sites, making them free for their patrons.
We also suggest that you contact the Alabama Department of Archives and History to request a search for registers of births and baptisms as well as state census records. The Marshall County Alabama Archives may hold records relevant to your research as well. Please note that Alabama state law did not require counties to register births until 1881 and did not require a birth certificate until 1908.
Regarding the possibility Robert Harvey Jeans was adopted, we suggest you contact the offices of the clerks of probate courts in Alabama and the 27th Circuit Court of Alabama to request information regarding adoption records, marriage licenses, and wills. In your inquiries you may wish to note any name variants or broaden your search for the surrounding years. In addition, the FamilySearch Research wikis for Alabama Vital Records and Alabama Adoption Research as well as NARA’s Resources for Genealogists and the History Hub Blog titled Suggestions and Advice for Family History Researchers may be useful.
We hope this is helpful. Best of luck with your research!