Parental loneliness, parental stress and child mental health during the COVID-19 pandemic: Variations by cumulative socioeconomic risk

•Parents were suffering from stress and loneliness because of COVID-19.•Parental loneliness and stress were associated with child mental health.•Associations between parent and child mental health were stronger in disadvantaged families. The COVID-19 pandemic has raised concerns about parent and child mental health, especially within disadvantaged families. However, little is known about how parental stress and loneliness during the pandemic influenced their children and no studies have investigated if these associations could vary by socioeconomic status. In July to September 2021, a large representative sample of parents (N = 4,524) in Québec (Canada) reported on aspects of their own mental health and that of their 9–10 year old child. Outcome variables were child externalizing and internalizing symptoms. Exposure variables were changes in parental loneliness and parental stress since the onset of the pandemic. The moderator variable was cumulative socioeconomic risk. Multiple linear regression analyses were executed and adjusted for confounding factors. Child internalizing symptoms were associated with higher levels of parental stress (β = 0.14, p