If a child is experiencing nighttime crying, there are several things parents can do. First, give your child a calcium and vitamin D supplement, as many children experience nighttime crying, often due to vitamin D deficiency rickets. This is seen in younger children, especially those under 2 years of age. A blood test for vitamin D and calcium levels will clearly show that the child’s blood vitamin D and calcium levels are below the normal range. Vitamin D and calcium supplements should be given to the child promptly. Calcium supplements such as oral calcium gluconate or calcium carbonate granules are commonly used. Secondly, give the child the adjustment of gastrointestinal dysfunction. The reason why the child appears to cry at night is caused by gastrointestinal discomfort. Often there is abdominal pain, undigested food in the stool and so on. In this case, parents need to timely apply probiotics to the child to treat, commonly used probiotics can choose small Peifikang, mamma love and so on.