Aim: To evaluate the validity and reliability of the Turkish adaptations of the Children's Comfort Daisies (CCD) and the Children's Comfort Behavior Checklist (CCBC), developed by Kolcaba & DiMarco in 2005, which have been culturally adapted into only one other language. Design: This methodological study followed pediatric research guidelines using the Child-Centred Research Checklist from the EQUATOR Network. Methods: The study was conducted between November 1, 2024, and February 1, 2025, in a pediatric ward in northwestern Turkey. It included 151 patients aged 0-18 without analgesics or sedatives within the past four hours. Content validity was assessed using the Davis technique, and construct validity was evaluated by factor analysis. Internal consistency was measured with Cronbach's alpha, inter-rater reliability with Cohen's kappa, and test-retest reliability by evaluating scores 15 min before and after an invasive procedure. The correlation between CCBC and CCD was analyzed using Spearman's Rho. Results: The mean age of participants was 7.11 +/- 4.92 years, with 60.9 % being male. The CBC, which has 30 items with five categories, demonstrated an appropriate factor structure, valid content, good internal consistency, and acceptable inter-rater reliability. The visually scored CCD demonstrated acceptable goodness-of-fit indices. A strong correlation and high agreement were found between the two scales. Conclusions: The Turkish versions of CCBC and CCD are valid and reliable scales for assessing comfort in children with acute illnesses. This study addresses the current lack of culturally adapted comfort assessment scales in Turkey by developing and validating the Turkish versions of the CCBC and CCD. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.