47) You see a 2-month-old infant in the emergency department f | Paediatrics videos & books

47) You see a 2-month-old infant in the emergency department for vomiting. The mother says that the baby has been spitting up more over the past few days and has become more irritable. She denies any fever, diarrhea, or change in formula. The mother tells you that there is a family history of “heartburn” and that her other children have all spit up. The infant has some emesis in the emergency department that seems to be formula mixed with some bile. The infant is intermittently irritable and sleepy.
What is the most concerning diagnosis that this could be?