<p>Although there are many studies in the literature that have studied the quality of life and nutritional status of people with celiac disease, research on the status of their healthy siblings in this process is quite limited. The study was conducted with children diagnosed with celiac disease, their healthy siblings, and healthy children of similar age. Data were collected using the Sociodemographic Information Form, the Children and Nutrition Assessment Form, and the Quality of Life Scale (Kid-KIDNL). The food consumption status, nutrient adequacy levels, anthropometric measurements, and quality of life of the participants were analyzed. The study consisted of celiac (<i>n</i> = 81), sibling (<i>n</i> = 78), and control (<i>n</i> = 106) groups, with similar age and gender distributions. Only protein consumption of the celiac group was higher, but the three groups did not show a significant difference in terms of nutrient adequacy. Among participants with similar heights, body weights (<i>p</i> = 0.030 and <i>p</i> = 0.031, respectively) and BMI in the celiac group were lower than those of siblings and controls (<i>p</i> &lt; 0.001 and <i>p</i> = 0.041, respectively). No significant difference was observed in the total scores of the Kid-KINDL scale. However, evaluation of the subscale scores revealed statistically significant differences between groups in the self-esteem (<i>p</i> &lt; 0.001), friends (<i>p</i> = 0.007), and school (<i>p</i> &lt; 0.001) dimensions. Additionally, a significant difference was found between the groups regarding overall quality of life levels (<i>p</i> = 0.040). Notably, 40.0% of children in the celiac group were identified as having a low quality of life.</p><p> <i>Conclusion</i>:&#xa0;While overall nutritional adequacy was similar across groups, children with celiac disease and their siblings exhibited lower self-esteem scores compared to controls. These findings indicate that, alongside nutritional monitoring, family-centered psychosocial support is essential for both patients and their siblings.<Table Float="No" ID="Taba"> <tgroup align="left" cols="2"> <colspec align="left" colname="c1" colnum="1" /> <colspec align="left" colname="c2" colnum="2" /> <tbody> <row> <entry nameend="c2" namest="c1"> <p><b>What is Known:</b></p> <p>• <i>Children with coeliac disease may exhibit persistent nutritional inadequacies and psychosocial challenges despite adherence to a gluten-free diet.</i></p> <p>• <i>The psychosocial well-being of healthy siblings can be affected by the family dynamics associated with chronic disease.</i></p> </entry> </row> <row> <entry nameend="c2" namest="c1"> <p><b>What is New:</b></p> <p>• <i>This study provides a comparative evaluation of nutritional status and quality of life among children with coeliac disease, their healthy siblings, and healthy peers.</i></p> <p>• <i>While overall nutritional adequacy was similar across groups, children with coeliac disease and their siblings exhibited lower self-esteem compared to controls, indicating that family-centred psychosocial support should accompany nutritional monitoring.</i></p> </entry> </row> </tbody> </tgroup> </Table></p>