Six-month old patient who underwent split liver transplantation for biliary atresia. Eleven days after transplantation, because of the onset of fever, an ultrasound scan of the abdomen was performed demonstrating a subphrenic fluid collection (1). Under ultrasound guidance a pig-tail drain was positioned in the collection with drainage of bile-like fluid (2). Fifteen days later, ultrasound control revealed resolution of the collection and the drain was removed (3).