When should doctors seek protective custody to override a parent’s refusal of potentially lifesaving treatment for their child? The answer to this question seemingly has different answers for different subspecialties of pediatrics. This paper specifically looks at different thresholds for physicians overriding parental refusals of life-sustaining treatment between neonatology, cardiology, and oncology. The threshold for mandating treatment of premature babies seems to be a survival rate of 25–50%. This is not the case when the treatment in question is open heart (...) surgery for a child with congenital heart disease. Most cardiologists would not pursue legal action when parents refuse treatment, unless the anticipated survival rate after surgery is above 90%. In pediatric oncology, there are case reports of physicians requesting and obtaining protective custody for cancer treatment when the reported mortality rates are 40–50%. Such differences might be attributed to differences in care, a reasonable prioritization of quality of life over survival, or the role uncertainty plays on prognoses, especially for the extremely young. Nonetheless, other, non-medical factors may have a significant effect on inconsistencies in care across these pediatric subspecialties and require further examinations. (shrink)