Q. A 3-year-old boy is brought to your clinic for short stature. The mother mentions no family history of bone conditions. The parents have an acceptable height. The family immigrated to the United States from Latin America around one year ago. The patient was exclusively breastfed until age six months and has since had a varied diet of fruits, vegetables, and meats. He has not received any supplements and currently takes no medications. He has three elder siblings with no skeletal problems, and their heights are normal. Vital signs are normal. Physical examination reveals a lethargic child with dental enamel defects, bilateral varus bowing of legs and bilateral, symmetric, bead-like enlargement of the costochondral junctions. What do you expect to find in his lab tests?