If you want to determine whether your baby is calcium deficient, you can do so in two ways: 1) observation of your baby in daily life, for example, if your baby is calcium deficient, there will be night sweats after sleep, that is, sweating profusely, and if your baby is calcium deficient, there will be skeletal manifestations such as square cranium, occipital baldness, rib cage exostosis or chicken chest, etc. You can determine whether your baby is calcium deficient by observing the growth and development of your baby. 2) you can directly take your baby to the hospital for blood tests. The blood test can check trace elements such as calcium, iron, zinc, copper, magnesium and lead, etc. The test of trace elements can clarify whether the infant has calcium deficiency. According to the above two points can be judged, according to the actual situation can be supplemented accordingly.