Objectives: This study aimed to adapt and validate the Parents’ Evaluation of Aural/Oral Performance of Children (PEACH) questionnaire for Greek-speaking children aged 1 to 6 years. Key objectives included assessing the PEACH questionnaire’s reliability and validity and determining if children from Greece and Cyprus exhibit similar auditory performance, which would suggest they belong to a comparable population. Methods: This cross-sectional study involved 87 children from monolingual Greek-speaking households in Greece (N = 38) and Cyprus (N = 49), all full-term with typical hearing and no cognitive or language deficits. The children’s ages ranged from 12 to 82 months. The study used an independent samples t-test to compare PEACH Overall Scores between Greek and Greek–Cypriot children. Internal consistency was assessed with Cronbach’s alpha and item-total correlations for each country. Additionally, regression models examined the relationship between PEACH scores and age. Results: Greek–Cypriot children had significantly higher PEACH scores (92.09%) than Greek children (86.71%), t(85) = 2.31, p = 0.023. The Cronbach’s alpha for the Greek sample was 0.92, indicating a strong internal consistency, while the Greek–Cypriot sample had a lower alpha of 0.79, with item-total correlations ranging from 0.16 to 0.75. Normative curves showed that auditory performance in the Greek sample increased sharply until 40 months, then plateaued until 60 months. In contrast, the Greek–Cypriot sample’s scores rose sharply until 25 months and plateaued by 40 months. Conclusions: The Greek-translated PEACH questionnaire demonstrated strong reliability and construct validity for Greek children, consistent with other language adaptations. However, the Greek–Cypriot sample did not achieve similar reliability, and differences in scores suggest potential cultural, linguistic, or environmental factors impacting auditory development. These findings emphasize the importance of regional adaptations in standardized assessments. Further research is recommended to explore factors contributing to these differences for more accurate assessments of Greek-speaking children.