The manifestations of calcium deficiency in a seven-month-old baby include: first, night terrors, night sweats, crying, and poor sleep. Second, the performance of the skull square skull. Third, ribs may have string gangrene or rib ectropion, delayed teething, scanty hair and so on are the manifestations of calcium deficiency. In addition to checking the blood calcium is lower than normal, you can take oral cod liver oil and calcium to prevent and treat rickets and prevent calcium deficiency. If severe calcium deficiency can appear bone deformity, such as O-shaped legs, X-shaped legs and chicken chest, so we should increase nutrition, eat more calcium-rich foods like kelp, milk, bone broth, etc. can increase calcium, effective prevention of pediatric calcium deficiency.