Does anyone have any spare time to correct my essay?

subject:
Do you agree or disagree: childhood is the happiest time of a person's life
My essay:
Most people mention their childhood as the happiest period of their lives. I, myself, agree with them. I will employ one personal experience and a comprehensive evidence to support my idea.
To begin with, most of my funny memories are based on my childhood. Believe it or not, all friends of mine confirm that my childhood memories are the happiest story they have heard. Among them, a memory is so funny which my friends ask me to relate it for them again and again whenever we meet. Twenty years ago, when I was ten years old, my friends and I was watching the cars which passed by our alley. Suddenly, a black Benz, it is a car brand, came in our view. I asked: "Mohamad! is this a Benz?" Before Mohamad answered, Hasan, another friend of mine, answered loudly: "The Benz is only white!" My childhood is full of such memories, and it is the happiest period of my life.
Moreover, children do not have any burden to be worried about. I do not know any heavy burden which children face except for light ones. Late Shari'ti, a prominent writer and philosopher in 20th-century Iran, has a fantastic motto: "I wish I was a child, when my only problem was losing my little pencil!" I tend to think the less burden you have, the happier you are. Considering this, it would be crystal clear which childhood is lack of big problems, hence is full of happiness.
In conclusion, from my point of view, childhood is the happiest period of lifetime. My childhood is full of funny memories that have made the childhood so funny to me. In addition, I firmly believe that the less problem you have, the happier you are. And, childhood is the time in which every one has least problems.