OBJECTIVE: To examine the bidirectional associations between adolescent siblings' alcohol use before and during the onset of the COVID-19 pandemic in Spring 2020 and whether youths' stress about missed social connections (i.e., social disruption stress) moderated these associations. METHOD: The sample consisted of 682 families (2,046 participants) with two adolescent siblings (older siblings: Mage = 15.67 years, 51% female; younger siblings: Mage = 13.14 years, 48% female) and one parent (Mage = 45.15 years; 85% female) from five Midwestern U.S. states. Siblings reported on their own drinking and social disruption stress before and during the onset of the pandemic via online surveys. RESULTS: Accounting for younger siblings' earlier drinking and other confounders, older siblings' prepandemic drinking predicted a greater likelihood of younger siblings' drinking during the Spring 2020 pandemic shutdown. This association was not moderated by younger siblings' social disruption stress. The association between younger siblings' prepandemic drinking and older siblings' drinking during the shutdown was moderated by older siblings' social disruption stress. Specifically, younger siblings' earlier drinking was more strongly related to older siblings' drinking during the shutdown if older siblings reported more social disruption stress. CONCLUSIONS: Siblings are important socialization agents of alcohol use during adolescence. Sibling interventions may be particularly salient during times of stress and isolation when youths' social interactions with peers may be limited. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
