Hybrid computational phantoms combine voxel-based and simplified equation-based modelling approaches to provide unique advantages and more realism for the construction of anthropomorphic models. In this work, a methodology and C++ code were developed to generate hybrid computational phantoms that cover the statistical distributions of body morphometry in the pediatric population. The pediatric phantoms of the Virtual Population Series (IT'IS Foundation, Switzerland) were modified to match target anthropometric parameters, including body mass, body length, standing height, and sitting height/stature ratio, determined from reference databases of the National Centre for Health Statistics and the National Health, and Nutrition Examination Survey. The phantoms were selected as representative anchor phantoms for the newborn, 1-, 2-, 5-, 10-, and 15-year-old children, and were subsequently remodeled to create 1100 female and male phantoms with 10th, 25th, 50th, 75th, and 90th percentile body morphometries. Evaluation was performed qualitatively by means of 3D visualization and quantitatively by analysis of internal organ masses. Overall, the newly generated phantoms appear very reasonably representative of the main characteristics of the pediatric population at various ages and for different genders, body sizes, and sitting stature ratios. The masses of the internal organs increase with height and body mass. The comparison of organ masses of the heart, kidney, liver, lung, and spleen with published autopsy and ICRP reference data for children demonstrated that they follow the same trends when correlated with age. The hybrid computational phantom library constructed opens up the prospect for comprehensive radiation dosimetry calculations and risk assessment for the pediatric population of different age groups and diverse anthropometric parameters.