There is no vitamin or pill that can make an individual grow taller, according to WebMD; children should eat a nutritious diet to ensure that have the required nutrients for growth. Pills that are specifically marked as "height enhancers" do not work and should be avoided.
Individuals who have a legitimate health problem that inhibits their growth may be prescribed growth hormone by their doctor. This is available as a shot, not a pill, and is only used in extreme circumstances.
Kids concerned with their growth should eat a variety of nutritious foods, get sufficient sleep and participate in physical activity to keep their body in the best shape for growing. To get the most from their height, individuals need to use good posture, as slumping is a sure way to look shorter.