The symptoms of calcium deficiency in children vary according to the stage, including irritability, soft fontanel and chicken chest. The details are as follows: 1. Initial stage: mostly seen within six months, it will be manifested as irritable, irritable, sweaty, shaking head, etc. 2. Active period: within six months, mainly cranial changes, the edge of fontanel is soft, touching will have pressure ping-pong ball-like sensation. By the age of seven or eight months, the head is square. Typically, rickets beads are formed at the ribs, and bulges are formed at the wrists and ankles, called bracelets. By about one year of age, “chicken breasts” are formed. In severe cases, a depression is formed at the lower edge of the chest called the costophrenic groove. O-legs or X-legs will form after the child starts to stand and walk. 3. Recovery period: After treatment and exposure to sunlight, the above symptoms and signs will gradually decrease or disappear, and the body will slowly return to normal. 4. Sequelae: Individual children with severe disease, mostly after the age of two, may have different degrees of bone deformities at the end of the severe disease. Children with symptoms of calcium deficiency need to go to the hospital to monitor the blood calcium value, avoid blind supplementation, and get more sunshine.