Q. A 3-week-old male infant is brought to the pediatric clinic by concerned parents due to poor weight gain and feeding difficulties. They mention that since birth, he has shown an increasing intolerance to his formula. On further inquiry, they mention that he was briefly hospitalized for a febrile episode, later identified to be due to E. coli sepsis. On physical examination, the pediatrician observes jaundice with notable hepatomegaly. Slit-lamp examination reveals bilateral cataracts, an unusual finding for an infant. Neurodevelopmentally, the infant seems to lag: he isn't tracking objects consistently and hasn't shown the expected social responses. Laboratory evaluations show abnormal liver function tests. A detailed family history reveals that a distant relative had a similar condition in infancy but the details are vague. What is the diagnosis?