How to Explain leg rest to a Five-Year-Old

http://dominickovfx806.angelfire.com/index.blog/1646694/the-ultimate-glossary-of-terms-about-leg-rest-adjustable/

It has helped tremendously. I only wish it was higher but otherwise I find my legs searching for it when I sit at my desk. It helps relieve the pressure on back of my thighs from the edge of the chair.