Janet Dewar played a vital role in Red Cross operations in both Honolulu and Siberia. Before departing for overseas service, she taught classes in hygiene and home care of the sick as part of Red Cross training efforts in Hawaii. In November 1918, she sailed with the second Hawaii unit bound for Siberia. Once in Vladivostok, Janet was assigned to the Refugee Hospital and later served as head nurse on the repatriation steamer Heffron, which carried nearly 900 Czech soldiers back to Europe. Her leadership during that mission helped ensure the well-being of troops recovering from years of war and imprisonment