Dehydration in Children: Dehydration in children can result from not drinking enough liquids, vomiting, diarrhea, or combination of these conditions. Causes of dehydration in children include viral, bacterial, or parasitic infections, diabetes, and increased sweating, and others. Symptoms include sunken eyes, decrease in urination, no tears when crying, dry mouth, lethargy, and irritability. Treatment at home includes proper fluid replacement. Some cases of dehydration are so severe they may require hospitalization.