The old bird bring his son to the height and then let it fall down.
The son asks “Father it’s hurt, falling from the height. Why are you so cruel, bring me up high just to let me fall down?”
The old bird says “Son, I do it… to teach you how to fly”
“And once you are able to fly… You can fly even more higher than it”
~Anonymous – Seem I ever heard it somewhere, but forgot the source, so I put anonymous~