Section 13 Of Part 1. Preliminary Provisions From California Probate Code >> Division 1. >> Part 1.
13
. (a) The degree of kinship or consanguinity between two persons
is determined by counting the number of generations separating those
persons, pursuant to subdivision (b) or (c). Each generation is
called a degree.
(b) Lineal kinship or consanguinity is the relationship between
two persons, one of whom is a direct descendant of the other. The
degree of kinship between those persons is determined by counting the
generations separating the first person from the second person. In
counting the generations, the first person is excluded and the second
person is included. For example, parent and child are related in the
first degree of lineal kinship or consanguinity, grandchild and
grandparent are related in the second degree, and great-grandchild
and great-grandparent are related in the third degree.
(c) Collateral kinship or consanguinity is the relationship
between two people who spring from a common ancestor, but neither
person is the direct descendent of the other. The degree of kinship
is determined by counting the generations from the first person up to
the common ancestor and from the common ancestor down to the second
person. In counting the generations, the first person is excluded,
the second person is included, and the common ancestor is counted
only once. For example, siblings are related in the second degree of
collateral kinship or consanguinity, an aunt or uncle and a niece or
nephew are related in the third degree, and first cousins are related
in the fourth degree.