Which of the following is considered a developmental alert in children?

The identification of a developmental alert focuses on significant indicators that may suggest a child is not meeting expected social or emotional milestones. In this context, the inability to laugh or appear happy is a key concern. Happiness and the ability to express emotions are fundamental aspects of early childhood development and are essential for social interaction. A child who does not display these emotions may be experiencing developmental delays and could benefit from early intervention or further evaluation.

Other responses may indicate typical or favorable development; for example, consistently following directions, rapid weight gain, and frequent vocabulary use reflect skills and growth that are generally associated with healthy development. Each of these behaviors is a positive sign of progress in a child's learning and emotional development, contrasting with the potential red flag indicated by a lack of happiness or laughter.