The reasons why babies are sleepy are as follows: 1, environmental factors, when the surrounding area is too noisy, indoor light is too strong, and the temperature and humidity is too high, too low, the surrounding environment makes babies feel uncomfortable, so they will cry and do not sleep. 2, the baby is sleepy, but cries and refuses to sleep, because the baby is too small, does not yet know how to fall asleep to relieve the body’s uncomfortable, crying is sleepy to the extreme, making the baby uncomfortable, uncomfortable The baby’s body is not well-equipped to handle the problem, but the baby can only express it in the form of crying. 3, if the parents do not feed the baby properly, resulting in indigestion or pent-up food symptoms, due to the discomfort of the abdomen, will also lead to sleepy phenomenon. 4, lack of vitamin D, resulting in insufficient intake of calcium, because the baby’s body lack of calcium, will lead to increased neural excitability of the baby, it is not easy to fall asleep, sleepy symptoms.