The purpose of this study is to determine if and how, the decisions of the Inter-American Court of Human Rights, concerning children’s rights, have influenced the legal systems of those American Countries that are subject to its jurisdiction, having ratified the American Convention of Human Rights. First of all, therefore, we will evaluate without claiming to be exhaustive, the impact on domestic legal systems of the pronunciations of the Court of San José, in relation to the protection of the rights of the children: our work will be to assess whether the criteria used in this sector by domestic courts are the same or differ from those used by the Inter-American Court of human rights. However, because of the vastness and heterogeneity of the legal structure of the 25 States members of the Convention, it was decided to focus mainly on two Countries, Brazil and Argentina, which besides being the most representative countries in South America, have an internal situation that can be defined as highly paradigmatic of the current legal framework of the whole Latin-American reality.