Blood Relations

Marriage between people who are closely connected by blood (consanguinity) has been forbidden by many cultures throughout history.

Consanguinity, literally meaning common blood, describes a family relationship between two individuals and is measured in terms of the degree of consanguinity. The degree is measured by counting the number of steps between two individuals in a family tree; thus, for example, you are one degree from your children; a brother and sister are two degrees apart - one step up to the common parent, another back down to the sibling.