["Journal of Research on Adolescence, Volume 36, Issue 2, June 2026. ", "\nAbstract\nAmidst the abrupt school closure due to the COVID‐19 pandemic, adolescents faced unexpected challenges. Drawing on data collected 1 week before, during, and 1 year after the first COVID‐19 school closure in Belgium, this study investigated (1) changes in life satisfaction, (2) whether parent–child relationship quality served as a protective factor during school closures over and beyond COVID‐19‐related concerns; and (3) differences among early adolescents (N = 124, Mage = 12.86, 40.3% girls, 0.8% nonbinary) from different ethnic and SES backgrounds. Results revealed a general decline in life satisfaction during school closure, independent of ethnicity and SES, with only partial recovery when schools reopened. Beyond general negative consequences of parental conflict, parental warmth had a stronger protective effect for youth from ethnic minority and lower SES backgrounds, and the harmful impact of COVID‐19‐related concerns was more pronounced among youth from ethnic majority backgrounds. The findings highlight how school closures reduced adolescents' life satisfaction, and point toward critical underlying mechanisms among adolescents from different ethnic and SES backgrounds.\n"]