A nurse is assessing children experiencing regression. Which of the following children should the nurse be concerned about?

Rationale: A. Regression in development for six months, especially in gross motor skills, is abnormal and concerning. It may indicate a neurological or developmental issue and requires further evaluation. B. Temporary regression such as incontinence during illness or hospitalization is common and expected. C. Sleep disturbances due to environmental changes like moving are normal for infants. D. Regression when starting daycare is a normal stress response and usually resolves.