Babies crying all the time may be related to physiological factors, or may be caused by indigestion, vitamin D deficiency rickets and other reasons. 1. Physiological factors: because small babies can not use language to express their needs, when the stomach is hungry or after urination and defecation, resulting in physical discomfort, they may show the phenomenon of always crying. 2. Indigestion: in infancy, the gastrointestinal function is still immature, the gastrointestinal system’s digestive ability is weak, if the parents feed improperly, such as a one-time amount of milk is too much, or frequent breastfeeding, it is easy to exceed the baby’s gastrointestinal tract’s own digestive ability, resulting in indigestion, causing abdominal distension, abdominal pain, you may show the phenomenon of crying all the time. 3. Vitamin D deficiency rickets: the disease can lead to increased neural excitability of the child, it may cause restlessness, always crying, but also can be accompanied by excessive sweating of the head, occipital baldness, easy to wake up during sleep and other symptoms. Infants always crying, may also be caused by other reasons, parents should promptly find the cause, if necessary, need to consult a doctor as soon as possible, after diagnosis of the cause, by the doctor’s guidance for treatment and conditioning.