Four-month-old babies do not sleep at night may be caused by hunger and other physiological reasons, to meet the baby’s physiological needs can be relieved. However, it may also be related to vitamin D deficiency, intestinal spasms and other pathologic factors, the causes are different, the treatment is different. Babies do not sleep at night may be hungry or overfilled, living environment is too hot and other factors, can affect the baby’s sleep, resulting in not sleeping at night. Parents should adjust feeding habits, control the amount of milk fed, and maintain a suitable temperature and humidity to keep the baby in a comfortable state, which will help him/her fall asleep. If the baby does not sleep at night due to vitamin D deficiency, the child may be accompanied by symptoms such as irritability and excessive sweating. Oral vitamin D can be taken as prescribed by the doctor, and calcium supplementation can be used if necessary. At the same time, it is necessary to increase the daily sun exposure time. Intestinal cramps can cause abdominal pain, vomiting and other symptoms, causing the baby to cry and not sleep at night. You can apply hot compresses to your baby’s abdomen and rub clockwise to relieve the pain, and if it persists without relief, it is recommended to seek medical treatment. Four-month-old babies may also have other reasons for not sleeping at night, after excluding physiological factors, they should seek medical treatment in time to avoid delaying their condition.