COVID-19 has affected people across the world. However, it has been suggested that individuals with Special Education Needs and Disabilities (SEND) and their families might have been particularly impacted by the first national lockdown in the UK. In contrast to previous studies, the current study examined wellbeing and anxiety at different time points and included a control group matched for family situation. Parents of 402 individuals with SEND reported on their own anxiety and wellbeing as well as that of their son/daughter at three time points (before COVID-19, when COVID-19 pandemic started, and during the national lockdown). In addition, data from 186 typically developing (TD) siblings was obtained. Repeated measures ANOVAs and regression analyses showed that, although both individuals with SEND and their TD siblings showed increased anxiety across the three time points, levels of anxiety were not predicted by age, gender or health. Instead, levels of anxiety in the SEND group, but not the TD siblings, were predicted by awareness about COVID-19, diagnosis of an existing anxiety disorder as well as parental anxiety. In addition, whilst TD individuals were reported to increasingly worry about social related issues as well as family related issues, those with SEND were reported to worry about issues related to school closures. These findings show that COVID-19 impacts the wellbeing of those with SEND differently to that of their TD siblings and that school closures have a particular effect on this group. Further implications for policy impact and interventions are discussed.