Growth modeling is a key aspect of statistical analysis, particularly in fields such as biology, economics, and social sciences. In primate development studies, ontogeny is a well-known phenomenon that skeletal growth tends to stop at a certain age. Bone dimension measures of over 1200 skeletal sets derived from the Cayo Santiago (CS) rhesus colony were recently collected by a collaborative effort supported through NSF grants. These measures provided a valuable resource for extending a knowledge model for primate skeletal development regarding ontogeny, and variations based on sex and matrilineal lineage. This paper presents initial results of a custom regression model proposed, as well as model comparisons with other popular models used in similar line fitting tasks. Related data analytics and visualization support as implemented in the CSViewer for Analysts system are also described.