PRoMPT BOLUS will determine which of two commonly used IV fluid types is most effective to treat children with sepsis. Patients with possible septic shock will be treated with one of two types of IV fluid, both of which are part of standard of care--0.9% saline or balanced fluids (including lactated Ringer’s solution or Plasma-Lyte)--along with the best locally available medical care available for their symptoms. Because sepsis is an emergency, patients may be enrolled with “exception from informed consent” unless they opt-out. However, subjects/families will decide if their data can be used in the study. We are not aware of any reason, at this time, why anyone with sepsis would not choose to participate if awake and able to take part in decisions about their care.