The word "relative" refers us in its etymology to the Latin "parens" and refers to all those who make up the family through biological, adoptive ties or in relation to the spouse's relatives.
A relative is a member of your family. His closest relatives are his father, mother, brothers and sisters. The closest, after them, are your grandparents, who are the parents of your parents. Your parents' brothers and sisters are your uncles and aunts. All the children of the latter are your cousins, which means that you are also their cousin.
Relatives can be ascending in a straight line (son, father, grandfather, great-grandfather) or descending (great-grandfather, grandfather, father, son) or by collateral line (brothers, uncles, nephews, cousins). As for the relatives by affinity in a straight line, we have the in-laws, the sons-in-law and the daughters-in-law; and online collateral to brothers-in-law. The spouses are not considered related to each other. There are also religious or spiritual relationships, such as the one between godparents and godchildren.
In other words, the degrees are the generations, the father being the first in terms of the ascending straight line and in connection with his son. Between father and son there is one generation, while between grandson and grandfather there will be two generations and, in each case, there will be a second degree.
In the specific case of the collateral line, to know the degrees between relatives it is necessary to add degrees until the common bond is located, for example, the degree between cousins is the fourth, because the third will be the nephew, preceded by the second, which is the brother.
Consanguinity kinship is the relationship that exists between people united by a blood bond, that is, they have at least one ascendant in common. The closeness in blood kinship is determined by the number of generations that separate the two relatives, and is measured in degrees, each degree corresponds to the separation between a person and his parents or children.
The kinship by affinity is the related bond that is established between a spouse and the blood relatives of the other or reciprocally, between a person and the spouses of their blood relatives. This requires a full assumption of responsibility by both spouses. The degree and line of affinity are determined according to the degree and line of consanguinity. That is, a person is related by affinity of all the blood relatives of his spouse in the same line and degree that this is his by consanguinity. Reciprocally, the spouses of a person's family members are related by affinity of the latter in the same line and degree as the blood relative of whom they are spouses.
