To determine whether your baby has calcium deficiency, you can look for clinical signs of calcium deficiency, such as slower growth and development, crying at night, occipital baldness, abnormal bone development, and so on. You can also test the calcium level in your baby’s body to determine if your baby is deficient in calcium. 1. Clinical symptoms: the height growth of the baby will slow down when the baby lacks calcium. If the parents are not very short, but the baby is very short in the small children of the same age, it is most likely due to calcium deficiency. In addition, calcium-deficient babies will also have bone deformities, such as x-shaped legs or o-shaped legs. The baby’s abnormal crying at night, pillow baldness, etc. should also be suspected of calcium deficiency. 2. Laboratory tests: When parents suspect that their baby may have a calcium deficiency, they should take their baby to the hospital for a calcium test in order to clarify whether or not the baby is deficient in calcium and to guide them on how to take calcium supplements. If parents suspect that their baby has a calcium deficiency, it is recommended that they consult a doctor in a timely manner and follow the doctor’s advice to carry out the relevant examinations, and do not use their own medication.