Happy people and happy children have high self-esteem. They are content and they have reasonable goals that they work to meet. When they fail at something they don’t get in a mad, depressive panic they think about what went wrong and try to change it so that next time it will be better.
This self-esteem or trust in themselves that happy children or happy people have doesn’t necessarily come naturally. They have either seen it work for others or someone has guided them through this process. They have been guided to feel in control of their goals and the way in which they pursue them. Their goals haven’t been dictated by others, they have set them themselves.