Some young sons suddenly cry at night when they are sleeping, causing young parents to panic and not know what to do. Instead of rushing to the hospital right away, it is better to settle down since and make careful observations to find out what the cause is. The most common causes of nocturnal crying in children are non-pathological. For example, hunger, thirst, holding urine or wet diapers, too cold and too hot, clothing too tight discomfort, mosquito bites, sharp things touching the skin or sleep posture is not good, causing pain and numbness in the limbs, breathing difficulties, etc., to find these causes and timely removal, the child can sleep quietly. In addition, children with certain diseases can also lead to sleep disturbances, the most common are the following: (1) rickets: children suffering from this disease sweating, irritable, easily startled, often crying at night. In this case, the child must be given calcium and vitamin D supplements under the guidance of a doctor, and usually let the child do more outdoor activities, receive ultraviolet radiation from the sun, and eat more vitamin D-rich foods, such as egg yolk and animal liver. (2) Intestinal spasm: If the child suddenly cries, struggles or rolls over at night, is pale, does not let others touch and press the abdomen, cries when it happens, the stomach is not distended, cannot feel the lump, and there is no vomiting, fever, diarrhea and other symptoms, this may be a manifestation of intestinal spasm. You can gently massage the abdomen and give belladonna orally in severe cases to relieve the spasms, usually pay attention to keeping the abdomen warm and eat less cold diet. If a child has the above-mentioned paroxysmal abdominal pain with vomiting, jam-like stools and palpable lumps in the abdomen, then the disease must not be delayed and must be sent to the hospital immediately. (3) Pinworm disease: If a child is asleep for 1-2 hours or suddenly cries and scratches the anus, parents should carefully observe under the light, such as around the anus to see white thread-like worms in activity, which is suffering from pinworm disease, in addition to deworming drugs, the most important thing is to pay attention to personal hygiene, diligent hand washing, nail clipping, not sucking fingers, do not wear crotch pants, bedding toys should be frequently dried to prevent their own reinfection.