Civil and Canon relationships:

"Civil" and "Canon" refer to the degree of a relationship. The degree of a relationship is a legal term. It refers to the number of "steps" between two people who are related by blood.

Canon law is used in most of the United States. It measures the maximum number of steps from the nearest common ancestor. For example, you would be 2 direct steps away from your first cousin because your nearest common ancestor is one of your grandparents. So in this case, the degree is 2. The degree in civil law represents the total number of steps through the blood line that separate two individuals. For example, there are 2 steps from you to your grandparent, and then 2 more steps back down to your first cousin, so the degree is 4.