If an infant is growing particularly rapidly and parents do not allow the child to get more sunlight and take vitamin D supplements, it is very easy for the infant to develop a vitamin D deficiency. The symptoms of vitamin D deficiency in children mainly include the following: firstly, children will have the symptom of excessive sweating, children with vitamin D deficiency will have more sweating at night and during the day, more sweating, especially more sweating on the head will cause occipital baldness in children; secondly, children will have the symptom of crying and restlessness at night, children with vitamin D deficiency will lead to a decrease in the amount of calcium absorption in the intestine, and too little calcium absorption in the body will lead to hypocalcemia. Hypocalcemia can lead to increased neuroexcitability, which can lead to restless sleep at night, repeated crying at night and sleep movement.