Misalignment of pulmonary veins with alveolar capillary dysplasia is recognized as a rare cause of persistent pulmonary hypertension of the neonate. Until now, misalignment of pulmonary veins was thought to be a random occurrence, but its appearance in siblings at our institution suggests that there may be a familial predisposition. There have been reports of variable expression and variable severity in this disease; our report describes this variability in family members.