The author reports that children’s understanding of facial expressions is poor and changes qualitatively and slowly over the course of development. Initially, children divide facial expressions into two simple categories (feels good, feels bad). These broad categories are then gradually differentiated until an adult system of discrete categories is achieved, likely in the teen years. Children’s understanding of most specific emotions begins not with facial expressions, but with their understanding of the emotion’s antecedents and behavioral consequences.
Widen, Sherri C. (2013). Children’s Interpretation of Facial Expressions: The Long Path from Valence-Based to Specific Discrete Categories. Emotion Review, 5, 72-77