In this Paper I’ll explore how legal categories about family are constructed and implemented. I will focus on the emergence and on the evolution of two categories: the equality between spouses and the interest of the child. On one hand, I will study the evolution of these notions’ meanings during the 20th and 21st century. On the other hand, I will explore how these notions constitute and give meaning to the definitions of what a father, a mother, a couple or a family is according to law. By adopting a sociohistorical perspective, I argue that these definitions are issues related to the competition between various social mobilizations struggling for their interpretation of the law. Ultimately, I show how social stakes about the legal regulation of the family are translated in law.
