A brief literature review of VDDR1A cases with CYP27B1 pathogenic variants clinically showed 59% failure to thrive/growth retardation, 38–41% delayed motor milestones/inability to walk, 13% poor feeding, 27% leg bowing, 16.5% seizure, and 13.6% fracture. The gene discussed is CYP27B1; the disease is Failure to thrive.