The causes of sudden crying in the sleep of newborns mainly include the following situations: Firstly, it is caused by the newborn’s bowel movements, after the newborn has defecated or urinated, there will be uncomfortable symptoms, there will be crying, thus reminding the parents of the newborn to change the newborn’s diaper in a timely manner. The second is due to abdominal pain, if the newborn has acute intestinal cramps, it will cause the newborn to suddenly cry in his sleep, for this case, you can apply probiotics to the newborn to regulate, for example, you can give the newborn to take small Pepcid, Mamie’s Love and so on. Then if the newborn is hungry, it will also appear to cry in its sleep, for this case, parents can feed the newborn in time.