The phenotypes and familial (segregation) results were consistent with Ornithine transcarbamylase deficiency [OMIM: 311250] with a X‐linked inheritance pattern, but the VUS (c.176T>C (p.L59P) in OTC gene) is predicted inconsistently (Tolerated for SIFT§ and Probably damaging for PolyPhen_2§). Here, OTC is linked to hyperinsulinemic hypoglycemia, familial, 4.