Crying of January babies may be related to environmental factors, improper feeding, calcium deficiency, gastrointestinal diseases and so on. 1. Environmental factors: If the indoor temperature is higher or lower, or if the baby is frightened, or if the diaper is not changed in time, etc., it may cause the January baby to be emotionally unstable and cry. 2. Improper feeding: If parents do not know how to feed, feed too much milk or feed too cold milk powder, it may lead to indigestion, abdominal pain, bloating and other symptoms, causing January baby crying. 3. Calcium deficiency: If the baby is not supplemented with vitamin D in time after birth in January, it may lead to calcium deficiency in the baby’s body. When January babies are deficient in calcium, it may lead to increased nerve excitability and crying. 4. gastrointestinal diseases: when the January baby intestinal spasm, gastrointestinal dysfunction, intestinal obstruction and other diseases, may lead to abdominal pain symptoms, cause crying phenomenon, and also accompanied by nausea, vomiting and other symptoms. January baby crying to rule out physiological causes, parents should take the baby to the hospital in a timely manner, clear specific causes, under the guidance of the doctor standardized treatment, so as not to delay the condition.