Critical illness and the therapies that accompany it are associated with a disruption in the ecological equilibrium of the GI tract that can ultimately lead to infection. Lactobacillus GG, a probiotic, replenishes the healthy flora of the intestinal tract and may decrease the risk of diarrhea and infection during critical illness. However, little is known about the impact of probiotics following a burn injury and the mechanisms behind the proposed benefits. The hypothesis of this research is that Lactobacillus GG decreases the incidence of diarrhea and infection in burned children receiving antibiotic therapy. The specific aim of this research is to determine the impact of Lactobacillus GG on the incidence of diarrhea and infection among burned children (>20% TBSA) receiving antibiotic therapy.