Background: The COVID-19 pandemic has impacted on all aspects of life. The physical health burden predominately impacts adults. However, the psychological burden has impacted significantly on the development and wellbeing of babies and young children. The aim of this research was to explore the impact of COVID-19 restrictions on vulnerable children (aged 0-6) and their families who were registered with a prevention and early intervention programme in an area of socio-economic disadvantage in southern Ireland. Methods: A convenience sample of 15 mothers were contacted by the staff from the multidisciplinary Infant Mental Health home visiting team. All participated in semi-structured telephone interviews. Two scales, the UCLA 3-Item Loneliness Scale and the Parental Stress Scale were included. A focus group was conducted with the home visiting team. Results: Parental concerns for their children related to six categories: altered behaviour; lack of services; social isolation; missed school; mental health; and physical health. Concerning behaviours regarding developmental regression, feeding, self-regulation, sleep and worrying new behaviours such as repetitive hand washing were reported. 27% of families experienced hunger during lockdown and staff raised concerns regarding substandard housing. Delayed or cancelled medical appointments included speech and occupational therapy, and developmental assessment. Loneliness and isolation were issues for parents. 67% scored greater than five on the loneliness scale. The mean stress score was 44 (range 37-56). Staff raised concerns regarding maternal mental health and highlighted the lack of services for parents. Conclusion: COVID-19 has had a disproportionate impact on vulnerable children. There is evidence of regression and issues regarding self-regulation and socio-emotional development. Lack of services and the offering of alternative appointments by phone resulted in loss of the crucial face-to-face contact with services. The pandemic has exacerbated inequalities in the early years and this is a crisis in the making.