A child’s constant crying may be related to environmental discomfort, gastrointestinal diseases, other diseases and other factors. 1. Environmental discomfort: When the child is in an environment with a lower or higher temperature or more or less clothing, due to the child’s poor regulation of body temperature and body fluids, it may cause discomfort such as overcooling, overheating, and so on, thus resulting in old cries, restlessness and other situations. 2. Gastrointestinal diseases: Due to the poor development of the gastrointestinal tract, when the child eats too much at one time, or is hungry for a long period of time, or eats allergy-prone food or hard-to-digest food, it may cause indigestion, lactose intolerance, allergy to milk proteins, and colic, which will lead to old crying and restlessness. 3. Other diseases: the child’s old crying may also be related to disease, when the child has a fever, nasal congestion, sore throat, abdominal pain, itchy skin and other symptoms, due to physical discomfort, will cause crying, this time you need to consult a doctor in a timely manner. In addition, the child’s calcium deficiency, growing pains and other factors may also cause the child to cry, parents are advised to take their children to the doctor in time to check, clear the cause of the disease for targeted treatment.