The eating habits of children and adults have been impacted by the COVID-19 pandemic, with evidence of increases in snacking and emotional eating, including eating to relieve boredom. We explored the experiences of families with children aged 4-8 years who had recently participated in a healthy eating pilot trial when the first national lockdown began in England. Eleven mothers were interviewed in April and May 2020. Interview questions were developed based on the COM-B model of behaviour. Four main themes were constructed using inductive thematic analysis. The first related to an initial panic phase, in which having enough food was the primary concern. The second related to ongoing challenges during the lockdown, with sub-themes including difficulties accessing food, managing children’s food requests, and balancing home and work responsibilities. The perception that energy-dense foods met families’ needs during this time led to increased purchasing of (and thus exposure to) energy-dense foods. In the third theme families described a turning point, with a desire to eat a healthier diet than they had in the early stages of the lockdown. Finally, in the fourth theme families reported a number of strategies for adapting and encouraging a balanced diet with their children. Our results suggest that even if parents have the capability (e.g., knowledge) and motivation to provide a healthy diet for their family, opportunity challenges (e.g., time, access to resources, environmental stressors) mean this is not always practical. Healthy eating interventions should not assume parents lack motivation, and should be sensitive to the context within which parents make feeding decisions.