Hemoglobin is the part of the red blood cell that carries oxygen, and so important for thriving. In the case of Brian, having 10.4 g/dL hemoglobin is very low. Normal values for hemoglobin in males range from 13.5 to 17.5 g/dL. The patient has very serious anema and note he is just 15 months old, and so needs immediate doctor’s attention. The doctor is likely to order a blood transfusion to elevate hemoglobin levels and stabilize the patient before ordering tests to determine cause of anemia.