Individuals and communities worldwide have been affected by COVID-19, resulting in stress and emotional instability. Families faced a massive disruption of daily routines, with increased psychological problems for both parents and children. In this cross-sectional study, we explored the emotional impact that health crises have had on Italian families, and in particular on mothers. Nine hundred and seventy-five Italian mothers of children aged 3–18 years participated in this study by completing a survey about maternal and child mental health. The mother’s psychological state was assessed using the GHQ and the PSS, while the children’s psychological state with the SDQ. We also collected family socio-demographic information. We conducted a path analysis through structural equation modeling on this data, with the hypothesis that socio-demographic variables and mothers’ psychological state were related, as well as mothers’ psychological condition and children’s well-being. Our results demonstrated how, during the lockdown, mothers reported a worsening in their psychological state. Furthermore, we found that both educational level and housing type were positively associated with maternal psychological well-being, while remote working was associated with decreased well-being. Maternal mental health had a strong relationship with reported children’s psychological problems. Mothers’ perceived stress was related to decreased prosociality and increased hyperactivity, emotional difficulties, and behavioral problems, while mothers’ general discomfort and depression were related to increased peer problems and emotional problems. This result supports helping mothers find a new balance between work, family, and children as a way to improve family functioning and well-being, as well as children’s mental health and resilience.