Tetralogy of Fallot is a congenital cardiac defect that has not been found to have a definite genetic relationship, meaning no chromosomal abnormalities have been discovered. However, congenital heart disease does tend to occur within families to a certain extent, indicating some level of familial predisposition. The primary cause, however, is believed to be related to viral infections during the first three months of pregnancy or the use of certain medications. Therefore, we believe that parents of a child with Tetralogy of Fallot can consider having a second child.