Eight-month-old babies who do not sleep soundly and cry at night should be alerted to the following reasons: First, the baby is not full and hungry, which will cause the child to sleep soundly. If this is the case, parents should strengthen the feeding and add supplementary food to the child on time. Second, abdominal pain, if the baby has vomiting, diarrhea, abdominal distension and other manifestations, it is possible that the child will have abdominal pain. Parents are advised to give the child appropriate oral probiotics, or give the child a hot compress, massage and other treatments. Third, vitamin D deficiency rickets. Children with vitamin D deficiency rickets will show symptoms such as irritability, irritability, restless sleep and excessive sweating. If you suspect that your child is vitamin D deficient, it is recommended that you get a vitamin D test and give your child proper vitamin D. In addition, your child should get more sunlight, which can promote the production of vitamin D.