Final answer:
In pediatric units, identifying signs of possible abuse, such as unexplained bruises, is essential for reporting and ensuring child safety.
Explanation:
Child abuse and mandatory reporting are crucial responsibilities for healthcare professionals, including nurses in pediatric units. In the scenarios provided, the finding that should be followed up for possible abuse and mandatory reporting is the 3-year-old with forehead bruises that the mother attributes to running into a table. This is concerning as it may be a cover-up explanation for abuse, and healthcare providers have a duty to investigate further to ensure the child's safety.
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