"On the offensive end, when you're already in foul trouble, it's a fine line, " Anthony said.

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"It's a fine line between being perfect role models and being competitive - we must not lose the edge, " said Watson.

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"It's a very fine line you draw, whether it's new or it isn't, " says Peter Appelbaum , a pathologist at Hershey Medical Center and a professor at Pennsylvania State University.

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