Nine-month-old babies always cry at night, consider with dietary factors, environmental factors, may also be rickets. 1. Dietary factors, if the nine-month-old baby eats less, sleep during the hungry may appear always crying symptoms, at the same time if eating too much, indigestion may also lead to this situation. 2. Environmental factors, sleeping process if the environment is too noisy or strong light, high temperature, may affect the baby sleep, the symptoms of always crying at night. 3. Rickets, if the baby’s body lacks calcium and vitamin D, rickets may occur, resulting in night crying, excessive sweating, pillow baldness and other symptoms. Nine-month-old baby always crying at night, there may be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.