Family functioning buffers the consequences of the COVID-19 pandemic for children's quality of life and loneliness.

COVID-19 resulted in mass quarantine measures early in the pandemic. This disruption of daily life widened inequities and made children one of the most vulnerable populations during the crisis. This national, cross-sectional "COVID-Kids" study collected data from almost 500 parent-child dyads using standardized measures to better understand the effects of COVID exposure and impact on children's quality of life and loneliness. Data were collected social media from May to July 2020. According to parent proxy and child self-report, United States children experienced worse quality of life ( < 0.0001;  = 0.45 and 0.53) and greater child-reported loneliness ( < 0.0001) when compared to normative, healthy samples (i.e., children who do not have a chronic medical condition). Older children ( = 0.16,  = 0.001) and female children ( = 0.11,  = 0.02) reported greater loneliness. Higher child-reported family functioning scores were associated with better quality of life ( = 0.36,  < 0.0001) and less loneliness ( = -0.49,  < 0.0001). Moderated mediation analyses indicated the indirect effect of parent COVID impact on the association between COVID exposure and child quality of life was weaker in the context of better family functioning. Results of this study raise concern for the short-and long-term sequelae of the pandemic on the physical and mental health of children. Healthcare providers and researchers must find new and innovative ways to protect the well-being of children. Strengthening family functioning may buffer the effects of the pandemic and improve overall quality of life in our "COVID Kids."