Mitigating the adverse physical health risks associated with COVID-19 has been a priority of public health incentives. Less attention has been placed on understanding the psychological factors related to the global pandemic, especially among vulnerable populations. This qualitative study sought to understand the experiences of children and adolescents during COVID-19. This study interviewed 48 families during the COVID-19 pandemic restrictions, and a national lockdown, to understand its impacts. The study used an Interpretative Phenomenological Analysis (IPA) methodology. Parents and children discussed the negative impact of the restrictions on young people’s wellbeing. Children and adolescents experienced adverse mental health effects, including feelings of social isolation, depression, anxiety, and increases in maladaptive behaviour. Families with children with Autism Spectrum Disorders reported increased mental health difficulties during this period mostly due to changes to routine. The findings highlight the impact of severe restrictions on vulnerable populations’ wellbeing and mental health outcomes, including children, adolescents, and those with Autism spectrum disorder (ASD).