Objective: This study aimed to understand how periodic shifts infinancial cutbacks and fears of contracting COVID‐19 contributed to children’s externalizing behaviors due to increases in maternal stress among low‐income Latina mothers during the first 10 months of the COVID‐19 pandemic. Background: The COVID‐19 pandemic caused widespread health, economic, and psychological consequences for families and children. The Latino community is particularly vulnerable to the economic and health risks of this pandemic as a consequence of systemic oppression. The family stress model suggests that these family stressors will have psychological repercussions to parents, and downstream behavioral consequences to children. Method: We examined both the within‐ and between‐person impacts of worry surrounding contracting the virus and the economic consequences of the pandemic on maternal stress and child externalizing behaviors. Participants were 73 Latina mothers who completed assessments an average eight times across the first 10 months of the COVID‐19 pandemic. At each assessment time, the mother was asked about worries surrounding contracting the virus, economic cutbacks the family was making, her perceived stress, and her child’s externalizing behaviors during a brief phone call. Results: Between‐families, higher economic cutbacks indirectly increased child externalizing behaviors through maternal stress. The within‐family model revealed that at assessments when mothers expressed greater worry about contracting the COVID‐19 virus, they also reported greater stress. Further, at the within‐person level, a mother’s greater experience of stress was associated with greater reports of child externalizing behaviors, though the indirect association between COVID‐19 contract worry and child externalizing behaviors through maternal stress was not significant. Conclusions: Across the first 10 months of the COVID‐19 pandemic, the children in Latino families participating in this research exhibited more externalizing behaviors among families that engaged in more financial cutbacks as a function maternal stress. However, periodic spikes in Latina mothers’ fears of contracting COVID‐19 contributed to periodic spikes in stress, which predicted periodic spikes in child externalizing behaviors. Implications: Greater effort toward social policy that provides economic support for vulnerable families before periods of increased societal stress and greater protections for workers with limited sick leave and schedule flexibility will help promote resilience to future crises among low‐income Latino families.