Don't Take Anything for Granted, Son I prefer, "Take Nothing For Granted, My Son"

You know son, I love you. Your family loves you. You are just starting your life as I was did years ago. I was also a kid like you, as you are now. Times goes fast. One day, in a glance an twinkling of an eye, you will be as old as I am now. There is no time to waste. There are some tips, advice that I received from my father gave me when I was at your age and now I would like transmit 1 am going to tell it to you. Today, I give you one of these advices. One advice to really grow, in knowledge and as human being, that really helped me, is: "Don't take anything for granted". Remember this and you will grow into a wonderful human being.  We have, in a short span of time, many things to learn in this short life of ours and we are never going to know everything. will never know everything, for sure. If you accept, Acceptance without thinking , and without analyzing what is told to you,  other tells you, never will you don't improve in knowledge. Always try, My son, to you must always think and understand.  Ask if you don't.  , by yourself, without being Never be arrogant and believe you know everything. Be humble. Be flexible as situations change. your mind, if necessary. Accept that you are wrong whenever you see strong arguments or facts in contrary. When you are in the wrong, accept it and say sorry.  It takes more of man to be able to apologize.

Keep in mind that when you think you know, you stop learning. Keep thinking, keep researching and analyzing about everything you are interested in, for all your life. Do always your best and you will succeed in everything you do and you will have a fulfilled and happiest life. 2 My son, life is a process of learning.  The only time you stop learning is when you are six feet underground.  Give your best and be satisfied.  For there is always someone who is better than you are.  Satisfaction will give you happy and fulfilled life.

Thanks for your corrections and comments. 

1.  Transmit is too formal a word to be used in a situation between family members or friends.  It is fine if it is between the master and his student.  Besides, you son is too young to understand such difficult words.  Also I would like to change the structure of the sentence to something even warmer, "My son, your grandfather once gave me some advice which I am now going to tell you."

2.  This is too long winded and redundant.  You have said this earlier in a different way.  Even an adult will get bored by it, let alone a child.  Use the space and time to say something different.