An extramarital union generally refers to the life of two people in a close and lasting relationship without formal establishment, and Croatian legislation defines it as a life partnership between an unmarried woman and an unmarried man that lasts for at least three years, or shorter if a child is born within it. This type of union is becoming increasingly common in modern society. The extramarital union represents a complex and dynamic form of family life that requires careful consideration of legal and social aspects, with particular emphasis on the welfare and rights of children within the union. Parental care encompasses the rights and obligations of parents toward their children, including decisions about upbringing, education, health, and daily life. Parental care in extramarital unions is a challenging and complex aspect of family law practice, especially in circumstances of its termination. In these relationships, extramarital partners are equated with marital partners, just as children born out of wedlock are fully equal to children born within marriage, so parents share common obligations and responsibilities directed toward the child. This paper will, through literature analysis, seek to provide a comprehensive insight into the topic of extramarital unions and parental care. The aim of this paper is to analyze the legal and social aspects of extramarital unions with a focus on parental care. The paper will explore the legal frameworks currently in force in the Republic of Croatia concerning the rights of parents and their children and the challenges faced by parents of children in extramarital unions.