Cousins are divided into two categories, one is the daughter of my aunt, and the other is the daughter of my mother's brothers and sisters. Although they are all cousins, my aunt's daughter is closer because my aunt has the same surname as you.
In addition, cousins are three generations of collateral blood relatives, close relatives, but not immediate relatives. Immediate relatives refer to people who have direct blood relationship or marriage relationship with themselves, that is, immediate blood relatives and immediate in-laws, such as spouses, parents, children, grandparents (grandparents) and grandchildren (grandchildren).
Cousins refer to the little daughters of aunts, aunts and uncles, all of whom are cousins;
Cousin is the youngest daughter of my uncle's family and my uncle's family. Both of them are their cousins.
Generally speaking, cousins are relatives and cousins are members of a big family. In real life, cousins are the main social relations members of the family.