Despite sparse pediatric data on the effectiveness of stress ulcer prophylaxis to prevent gastrointestinal (GI) bleeding, 60% of critically ill children receive these medications. This may have unintended consequences - increasing the risk of nosocomial infections - which may be more serious and common than bleeding these drugs are prescribed to prevent. A large randomized trial (RCT) is needed to assess the balance of these risks and benefits, to determine if a strategy of withholding stress ulcer prophylaxis in critically ill children is not inferior to a strategy of routine stress ulcer prophylaxis. RCTs in pediatric critical care are exceptionally challenging to complete; thus, a rigorous pilot RCT is crucial. The pilot may prevent pursuit of a trial that is ultimately not feasible - which is ethically and financially responsible. It is more likely that this carefully designed pilot trial will ensure that the larger trial we undertake is successful.