Hydronephrosis in a newborn in typically asymptomatic. It is one of the most common and usually benign anomalies detected on prenatal ultrasonography, with only a minority causing significant problem requiring urgent intervention. Grading systems are in place to classify hydronephrosis based on trimester and the antero-posterior diameter of the fetal renal pelvis. Albeit a cause for parental and physician anxiety, it is reassuring that most cases tend to be transient according to established literature, and may only require watchful waiting along with adequate follow up, the protocols for which are in place in most countries. Sometimes however, a large hydronephrosis could cause mass effect, pressing on the anatomically adjacent structures in the body, and could therefore present in ways not commonly thought of. We present a neonate with giant congenital hydronephrosis with feed intolerance resulting from duodenal obstruction. A brief description of the case is followed by a mini review.