Letter to the Editor: Interesting clinical observationTitle: Acute Exacerbation of Graft-versus-Host Disease following SARS-CoV2 infection after Hematopoietic Stem Cell Transplant in Two Pediatric PatientsRunning Title: Graft-versus-Host Disease and SARS-CoV2 infectionAuthors: Michelle Choe1,2* Caridad Martinez1,2, Robert Krance1,2, Erin Doherty1,2ORCID:Michelle Choe: 0000-0001-9850-9435Institutional Affiliation:1 Hematology and Cancer Center, Texas Children’s Hospital, Houston, Texas2 Department of Pediatrics, Baylor College of Medicine, Houston, Texas*Corresponding Author:Michelle Choe, MD6701 Fannin St. Ste. 1510Houston, TX 77030P: 832-822-4242F: 832-825-1453Abbreviations key: