Because the child may not always seem sad, parents and teachers may not realize that the behavior problem is a sign of depression.

因为小孩可能并不总是看起来悲伤，而父母和老师可能没有意识到这种行为问题是抑郁症的征兆。

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Sheen has a long history as a problem child and I am not defending either his self-destructive or violent behavior.

FORBES: Charlie Sheen And Public Company Disclosure