This article examines family involvement and English learners' academic, behavioural and socioemotional outcomes through a synthetic analysis of 28 empirical studies (conducted between 1991 and 2019, mostly in the United States) with participants from kindergarten, elementary (primary), middle and high schools. These studies considered family involvement under spontaneous (non-interventional) and interventional conditions. Two types of studies (observational and experimental) were analysed to understand the relationships between one or more kinds of parental involvement and children's outcomes. For the observational studies (21), the authors conducted a meta-analysis of effect sizes by measuring Pearson's r correlation coefficient. Since most studies reported multiple effect sizes, the authors used a robust variance estimation (RVE) approach with correlational weights to handle the statistical dependency in their overall and moderator analyses. Due to the small number of experimental studies (7), a quantitative measurement of effect size was not feasible for these; therefore, the authors used a systematic review to report their findings on this part of their sample. For the observational studies, the random-effects model reported a positive, yet small effect size of [r-bar] = 0.15. The strongest associations between family involvement and children's outcomes were found when parents/caregivers had high educational expectations ([r-bar] = 0.22, p < 0.01) and encouraged aspiration in their children ([r-bar] = 0.22, p < 0.01). The experimental studies reported 26 positive effects against three negative effects. Overall, the authors' findings suggest that family involvement is associated with improved outcomes for English learners in academic, socioemotional and behavioural domains.