Commentary: Assortative parenting and assortative cross-parenting: New views of parental preference for selected children.

The commentary delves into the implications of "assortative parenting" and "assortative cross-parenting," as introduced by N. L. Segal, and situates these concepts within the framework of current research. It addresses the joys and complexities of raising twins, highlighting how their concurrent development stages can amplify parental favoritism and heighten the challenge of addressing each twin's unique needs. This interplay provides a rich context to investigate assortative parenting practices. Additionally, this paper contemplates the broader picture of twin studies, particularly how the care of monozygotic twins (who share 100 % of their genes) and dizygotic twins (who share 50 % of their genes, on average) may reveal the intertwined nature of genetics and environment in parenting strategies. It also proposes that twins' interactions with other family members, their spouses, and peers can offer profound insights into the phenomena of phenotypic assortative affiliation, enriching our understanding of close relational bonds.