Abstract
Ethnic-racial identity (ERI) formation is an important developmental task. Although families are a primary context for ERI socialization, little is known about siblings' role. Accordingly, we applied the Actor-Partner Interdependence Model to longitudinal data from 2 siblings to examine the links between siblings' ERI exploration, resolution, and affirmation. Participants were Mexican-origin mothers, fathers, and 2 siblings (older siblings Mage = 20.65 years; younger siblings Mage = 17.72 years) from 246 families in Arizona who were interviewed on 2 occasions across 2 years. Siblings' ERI exploration in late adolescence positively predicted young adult ERI, accounting for mothers' and fathers' ERIs. For resolution, the sibling (i.e., partner) effect was moderated by sibling gender constellation, such that the sibling effect emerged only for same-sex dyads. For affirmation, the sibling effect emerged for older but not younger siblings. These findings highlight the need to understand siblings' role in ERI and to expand research on family socialization of ERI beyond parents. (PsycInfo Database Record (c) 2021 APA, all rights reserved).