Objective: The COVID-19 outbreak has negatively affected children in many ways. This study aimed to compare the psychological responses of children exposed to different levels of stress during the COVID-19 outbreak. Methods: The anxiety levels, negative thoughts, and quality of life of COVID-19-positive children with COVID-19-positive parents (Child+ group, n=17), COVID-19-negative children who are separated from COVID-19-positive parents (Parent+ group, n=59), and a control group (n=64) were compared. The participants completed the Screen for Child Anxiety and Related Disorders (SCARED), Children’s Negative Cognitive Errors Questionnaire (CNCEQ), and Pediatric Quality of Life Inventory (PedsQL). Results: The statistical analysis revealed that the Parent+ group recorded higher SCARED and CNCEQ scores and lower PedsQL scores in comparison with the control group. No statistically significant difference was found between the scores of the Child+ and control groups. Furthermore, high CNCEQ scores and low PedsQL scores in the Parent+ group predicted an increase in their SCARED scores. Conclusion Our study indicates that separating children from their parents during the COVID-19 outbreak negatively influences their mental health and increases their anxiety levels.