Only a few years ago, physicians had to rely on pediatric patients' families to disclose whether children were the result of a consanguineous relationship. Having parents who are closely related is known to cause intellectual or developmental disabilities and congenital anomalies in offspring. Now, an array-based genetic test that clinicians routinely perform on children presenting with these symptoms negates the need for such confessions by showing spans of homozygosity that clearly indicate incestuous parental relationships.