Dear Mr. Martinez,
Thank you for posting your request on History Hub!
To determine when they arrived in the U.S. and when they became naturalized citizens, we suggest beginning with the U.S. census records. We searched the National Archives Catalog and located thePopulation Schedules for the 1890 Census; the Population Schedules for the 1900 Census, and the Population Schedules for the 1910 Census, the Population Schedules for the 1920 Census, the Population Schedules for the 1930 Census, and the Population Schedules for the 1940 Census in the Records of the Bureau of the Census (Record Group 29) that may contain information about Jose, Isabel, Rita Medina in Texas. The 1940 Census schedules are digitized and available using the Catalog. 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.
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.
In general, naturalization was a two-step process that took a minimum of five years. After residing in the United States for two years, an alien could file a "declaration of intention" ("first papers") to become a citizen. After three additional years, the alien could "petition for naturalization" (”second papers”). After the petition was granted, a certificate of citizenship was issued to the alien. These two steps did not have to take place in the same court.
Prior to September 27, 1906, any "court of record" (municipal, county, state, or Federal) could grant United States citizenship. Often petitioners went to the court most geographically convenient for them. As a general rule, the National Archives does not have naturalization records created in state or local courts. Please contact the Texas State Library & Archives Commission or the local courts for Dewitt or Cameron counties.
If a naturalization took place in a Federal court after September 27, 1906, naturalization indexes, declarations of intention (with any accompanying certificates of arrival), and petitions for naturalization will usually be in the National Archives facility serving the state in which the Federal court is located. Records of the Federal District and Circuit courts for the state of Texas are located at the National Archives at Fort Worth. For more information about these records, please contact the National Archives at Fort Worth (RM-FW) at email@example.com. No central index exists. To ensure a successful request with the National Archives, researchers should include: the name of petitioner (including known variants); date of birth; approximate date of entry to the US; approximate date of naturalization; where the individual was residing at the time of naturalization (city/county/state); and country of origin.
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 and RM-FW. We apologize for this inconvenience and appreciate your understanding and patience.
Lastly, we suggest that you contact the Texas Vital Records Department of the State Health Services to request a search for a birth certificate, as directed by the CDC page for Vital Records for the state of Texas. You may wish to note any name variants or broaden your search for the surrounding years. In addition, the FamilySearch Research wiki for Texas may be helpful.
We hope this is helpful. Best of luck with your family research!