If children are sleepy, it is often caused by a deficiency of the following trace elements and vitamins. The first is caused by a deficiency of the trace element iron, in children lacking the trace element iron, will often cause a decline in attention, mental state, and even cause serious iron deficiency anemia, when children often appear sleepy symptoms. The next symptom is caused by vitamin D deficiency in children, which can also cause sleepiness and often have pillow baldness and more sweating on the head. Lastly, the symptoms are caused by vitamin B deficiency in children, which can also cause sleepiness and often lip infections in children, and can be supplemented with vitamin B complex tablets.