Why is mental health important for youth development?

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Many mental illnesses are believed to be a genetic predisposition which is triggered by an environmental factor, leading to a disease state. People are particularly vulnerable when they are younger. In general, most mental illnesses could have a better prognosis the later the onset and the more rapidly the illness is identified. Therefore, paying close attention to children's mental health will result in better outcomes for children, even when the predisposition exists.