Babies crying on time in the middle of the night every day may be caused by hunger, overheating or overcooling, lack of calcium, bloating and so on. 1. Hunger: Since babies have a strong ability to digest breast milk, but babies have a small appetite, they need to be fed several times. If not fed within a certain period of time will produce hunger, which may cause the baby to cry punctually in the middle of the night every day. 2. Too hot or too cold: Because the blanket is too thick when sleeping, it may produce stifling heat, so the baby cries punctually in the middle of the night. If the blanket is too thin and the baby is too cold, the baby will also cry in the middle of the night. 3. Calcium deficiency: If the baby is deficient in calcium, it will lead to a decrease in blood calcium, causing an increase in the excitability of the brain’s vegetative nerves, which may lead to crying in the middle of the night every day. 4. Bloating: Because the baby ate too much before bedtime or did not burp after drinking milk, it may lead to the baby’s stomach bloating, appearing in the middle of the night on time crying. There may be other reasons for your baby to cry in the middle of the night, so we recommend that you go to the hospital in time for a complete examination to determine the cause of your baby’s crying, and then give targeted treatment or therapy.