In the United States of America, approximately 40,000 infants are born annually with congenitally malformed hearts. Children with defects that require complex surgical palliation, or definitive repair, face many challenges in achieving optimal short-term and long-term growth. The presence of associated chromosomal abnormalities, cyanosis, and cardiac failure adds to the complexity and challenge. In this review, we address three themes related to feeding, growth, and nutrition of infants after neonatal cardiac surgery: nutritional challenges after chylothorax; breastfeeding after surgery; and the challenges of feeding after discharge. Chylothorax is a rare complication following cardiothoracic surgery in children. Children with chylothorax have nutritional depletion secondary to protein losses in chylous fluid, hypovolaemia, and electrolyte losses. In spite of the evidence supporting the use of human milk and breastfeeding in preterm infants, barriers to its use appear to persist in infants with critical cardiac disease. Yet, human milk is the preferred form of nutrition for well, preterm, or ill infants. It is well documented that after complex neonatal cardiac surgery medical teams and families struggle with infant feeding problems. Parents have described feeding their children as difficult, time consuming, and anxiety producing. Medical complications such as chylothorax, limited access to human milk, and parental concerns and stress about feeding are but three of the myriad of factors that may contribute to poor outcomes regarding nutrition and growth. Compelling evidence exists that this multi-factorial problem must be addressed with both physiological and behavioural strategies.