Two-year-old babies cry in the middle of the night for the following reasons, pay attention to the following points: First, focus on whether the baby has vitamin D deficiency rickets, because calcium absorption becomes poor after vitamin D deficiency is prone to calcium deficiency, causing the baby’s increased neuroexcitability leads to crying at night. Second, pay attention to whether the baby has indigestion, poor absorption function caused by increased intestinal peristalsis, affecting the baby’s sleep. Third, pay attention to whether the baby is in the period of disease, such as respiratory diseases, rhinitis, sinusitis resulting in poor ventilation of the nose, bronchitis, pneumonia resulting in poor breathing, gastrointestinal discomfort caused by intestinal viruses, bacterial infections. Fourth, pay attention to whether the baby’s sleep environment is poor, such as too much light, too much noise, the quilt is not suitable.