A: If both brothers are tested, Orchid Cellmark will extend the genetic testing until we are able to distinguish between the brothers. However, if only one brother was tested, and our laboratory is not informed about the possibility of the other related alleged father, there is a possibility that the statistics we issue may not be strictly correct, because we assume that the other possible fathers are not related to the tested man. If our DNA laboratory is informed, after the testing, that a brother of the tested man might be the father, we can determine the odds that the tested man, not his untested brother, is in fact the true biological father. However, when brothers are both potential fathers of a child, we strongly recommend testing both brothers as well as the mother of the child.