How do our bodies develop as we grow older?

How do we go from 9 pounds and 1'0 ALLLLLLLLLL the way to adult sized. How do our bones and skin adjust to the growth. And what about organs?

How do our bodies develop as we grow older?
Our bones actually decrease as we get older. Example, we had more bones as a fetus that we have as a child and adult put together, but our bones grow by the use of growth hormones and the help of calcium. I suspect our organs get bigger and stronger (if we take care of ourselves) to meet the demand of our growing bodies. Our skin cells probably produces more skin cells to stretch the ouside skin as we grow toward adulthood.
Reply:Everytime I look in a full-length mirror, I realize that gravity conquers all.