Previous research has shown that critical periods of feeding skills development exist and feeding problems can arise in children due to delays in attaining feeding developmental milestones. This study aims to delineate the transitional process of feeding development in healthy children and children with gastrointestinal diseases (GIDs) and to examine the relationship between feeding milestones and the appearance of later feeding problems. A cross-sectional case-control study among 711 healthy Greek children and 119 children with GID, aged 2-7 years. Parents completed the Greek version of the Behavioral Pediatrics Feeding Assessment Scale and "self-reported" questionnaires assessing child's feeding history. Differences in feeding behavior of preschoolers between the 2 groups were found concerning the time of introduction of complementary (pureed), lumpy, and table foods as well as finger feeding and regular cup-drinking. Age-specific milestones as proposed by guidelines were not reached. Late introduction of complementary and lumpy foods (>6 months and >9 months, respectively) as well as finger feeding (>9 months) were predictive of more problematic feeding behaviors later on. The trajectory of feeding development, including less studied feeding milestones, both in healthy children and children with GIDs, indicates that there are discrepancies between current feeding practices and infant feeding guidelines, and a tendency to delay the acquisition of all assessed feeding milestones.