Definitions of degree of relationship
a measurement of a blood relationship (eg mother, son, sister etc), usually as either one vertical or one horizontal step in a standard family tree
They were not within prohibited degrees of relationship in relation to each other.
the closeness of one person to another, especially in a family or professional context eg between employee and franchisor
In Canada, a 'sufficient degree of relationship' between the employee and the franchisor is required in order for a franchisor to be held to be a 'common employer'.