A 2-year-old child crying in the middle of the night may be caused by fright, vitamin D deficiency, intussusception and other factors. 1. Scaring: If the child is frightened during the day or before going to bed, and the emotions are not well adjusted, the child may have nightmares at night, resulting in the child being awakened in the middle of the night and crying. 2. Vitamin D deficiency: if the child is picky about food, partiality of food, etc., it is easy to cause vitamin D deficiency, resulting in irritability, sleep disturbance, crying at night and other phenomena. 3. Intussusception: the child can be caused by the normal rhythm of intestinal peristalsis disorders and intussusception, resulting in sudden crying, and will be accompanied by vomiting, pallor, bloody stools and other phenomena. 2-year-old children crying in the middle of the night may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to determine the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.