Comparative Study of Preserving Sibling Cohabitation in Custody Determinations in French, United States, and Iranian Legal Systems

This article examines the legal rules governing the preservation of sibling cohabitation following parental separation in custody disputes across three legal systems: France, the United States, and Iran. The findings reveal that, in recent years, with growing emphasis on the fundamental principle of the best interests of the child, greater sensitivity has emerged toward maintaining and strengthening sibling bonds. The child’s interaction and relationship with siblings has thus come to be recognized as an essential element in best-interests assessments, reflected in both legislative policies and judicial practice, particularly in France and the United States. An analysis of Iranian case law further shows that perceptive judges, drawing on the available legal framework and judicial interpretation of the best interests principle— contingent upon the establishment of such interests —have sought to prevent separation among siblings in custody disputes whenever possible. Nevertheless, it is recommended that the Iranian legislature, in line with comparative practice, explicitly enumerate in an illustrative manner the key components for assessing the child’s best interests, including the preservation of meaningful sibling relationships. Moreover, given the developmental and emotional benefits of sibling bonds, judges should, in cases involving divided custody, fully utilize existing legal mechanisms to strengthen siblings’ relationships and ensure visitation rights. Ultimately, this study demonstrates that, despite variations in legal technique, a shared recognition of the child’s best interests is gradually emerging across the examined jurisdictions, offering a valuable foundation for the continued advancement of comparative family law scholarship.