64. From the arguments presented by the State, and from the evidence contained in the case file, the Court considers that at the custody trial the following aspects were discussed, inter alia: i) the sexual orientation of Ms. Atala; ii) Ms. Atala’s personality; iii) the alleged damage caused to the girls, and iv) the alleged precedence given by Ms. Atala to her interests. In addition, with respect to the girls’ father, arguments were presented in favor and against the question of whether he could offer them greater well-being. The State considered that the Inter-American Court should analyze all the evidence examined during the custody trial and not only the judgments issued by the domestic courts. 65. In this regard, the Court reiterates that international jurisdiction has a subsidiary,77 reinforcing, and complementary78 role, and therefore does not perform the duties of a “fourth instance” court. The Court is not an appeals body that must resolve disagreements between parties regarding some aspects of the assessment of the evidence or the application of domestic law in matters that do not directly concern compliance with international human rights obligations. Thus, this Court has held that, in principle, “it is up to the State courts to examine the facts and the evidence presented in individual cases.”79 66. Accordingly, it is not up to this Court to determine whether the mother or the father offered the three girls a better home, or to assess the evidence to that end, since this is outside the scope of the present case, whose purpose is to determine whether or not the judicial authorities have fulfilled their obligations under the Convention. Similarly, and based on the subsidiary nature of the Inter-American system, the Court is not competent to issue a ruling on the custody of the three girls M., V. and R., since this is a matter exclusively for Chile’s domestic courts. Therefore, the current custody of the minors is not the object of this case. 2. Prior consideration on the participation of the girls M., V. and R. 67. In the Decision of November 29, 2011 (supra para 12) the Court noted that the file contained no specific statements by the daughters M., V. and R. as to whether or not they agreed with the representation exercised by either of their parents or whether they wished to be considered as alleged victims in this case. The Court pointed out that although there were two briefs in which both the mother and the father stated that they were acting on behalf of the three girls before this Court, the position of the mother and the father did not necessarily represent the girls’ best interests. 68. Furthermore, in its Decision, the Court stated that children exercise their rights progressively, as they develop a greater degree of independence, and for this reason during early childhood their relatives act on their behalf. Clearly, the level of physical and intellectual development, experience and information varies widely among children. Therefore, when the hearing was held in accordance with the aforementioned Decision 77 Cf. Case of Acevedo Jaramillo et al. v. Peru. Interpretation of the Judgment of Preliminary Objections, Merits, Reparations and Costs. Judgment of November 24, 2006. Series C No. 157, para. 66 and Case of Cabrera García and Montiel Flores v. Mexico. Preliminary Objections, Merits, Reparations and Costs. Judgment of November 26 2010. Series C No. 220, para. 16. 78 The Preamble to the American Convention states that international protection is “in the form of a convention reinforcing or complementing the protection provided by the domestic law of the American states.” See also, The Effect of Reservations on the Entry into Force of the American Convention on Human Rights (Arts. 74 and 75). Advisory Opinion OC-2/82 of September 24, 1982. Series A No. 2, para. 31; The Expression "Laws " in Article 30 of the American Convention on Human Rights. Advisory Opinion OC-6/86 of May 9, 1986. Series A No. 6, para. 26, and Case of Velásquez Rodríguez v. Honduras. Merits. Judgment of July 29, 1988. Series C No. 4, para. 61. 79 Cabrera, para. 16. Case Nogueira of Carvalho et al. v. Brazil. Preliminary Objections and Merits. Judgment of November 28, 2006. Series C No. 161, para. 80 and Case Cabrera García and Montiel Flores, supra note 77, para. 16. 24