The Border Trade Alliance on October 18, 2021 sent this letter to the Department of Homeland Security that inquires about which documentation will be deemed acceptable proof of vaccination; how children under age 12, who are not eligible for vaccination will be treated when traveling with vaccinated guardians; whether the U.S. government will accept vaccines made by drugmakers other than Pfizer, Moderna, or J&J; and that argues for proper port of entry staffing to meet pent-up demand and, in the case of U.S. consulates in Mexico, adequate hours & staffing for the issuance of Border Crossing Cards.