I think that the ♥childhood is really the happiest time of people's life. As a child the things are simple. You have someone to take care of you and your only purpose in life is to do whatever you want to do. Who would not enjoy that? One may argue that as a grown up you have more ways to enjoy. But wait a minute... Being a grown up is a responsibility. Being a child is fun.
As the people grown up they start to realize the importance of their actions and the responsibilities they have. They start to be more cautious. That takes away the adventurous and experimentle element of the human nature, the flavor of life and the happiness is gone.
But the child have no such problems. He does not know anyhing about the world. And must find everything about it. Have you ever looked a childs face when he discovers something? He is smiling and laughing. Tell me that's not happiness. Of course at some point the child should find that the fire may burning him. But not everything is perfect though.
Tell me you do not want to treat you like a king. To have whatever you want to. Everyone around you to do whatever you want to, even if you need to cry a while. To be surrounded by people who loved you. But once upon a time you were like king. In your ♥childhood. As a child you were privileged to have all that as long as you do not have a younger brother or sister.
As you grown up a little more you start to communicate with kids of your age. And here comes the funniest part of your life. The games. And with the games comes the friends. And with the friends comes the craziest ideas, which you would turn into practise, in your life. To climb the trees, to break some windows or whatever your crazy little brain could think of. :)
Soon after that ray of pure child's creativity comes the school and little by little you start becoming a grown up. But every time you look back you start appreciating the chance you have had to be a kid and to do all the things you do. Then you suddenly realize that this was the ♥happiest time of your life♥