Background/Objectives: In children, gastroesophageal reflux disease (GERD) may lead to epithelial barrier dysfunction and the release of thymic stromal lymphopoietin (TSLP), interleukin-25 (IL-25), interleukin-33 (IL-33) and periostin, known as alarmins. The gene discussed is IL25; the disease is gastroesophageal reflux disease.