Despite theoretical claims that emotions are primarily communicated through prototypic facial expressions, empirical evidence is surprisingly scarce. This study aimed to (a) test whether children produced more components of a prototypic emotional facial expression during situations judged or self-reported to involve the corresponding emotion than situations involving other emotions (termed “intersituational specificity”), (b) test whether children produced more components of the prototypic expression corresponding to a situation’s judged or self-reported emotion than components of other emotional expressions (termed “intrasituational specificity”), and (c) examine coherence between children’s self-reported emotional experience and observers’ judgments of children’s emotions. One hundred and 20 children (ages 7–9) were video-recorded during a discussion with their mothers. Emotion ratings were obtained for children in 441 episodes. Children’s nonverbal behaviors were judged by observers and coded by FACS-trained researchers. Children’s self-reported emotion corresponded significantly to observers’ judgments of joy, anger, fear, and sadness but not surprise. Multilevel modeling results revealed that children produced joy facial expressions more in joy episodes than nonjoy episodes (supporting intersituational specificity for joy) and more joy and surprise expressions than other emotional expressions in joy and surprise episodes (supporting intrasituational specificity for joy and surprise). However, children produced anger, fear, and sadness expressions more in noncorresponding episodes and produced these expressions less than other expressions in corresponding episodes. Findings suggest that communication of negative emotion during social interactions—as indexed by agreement between self-report and observer judgments—may rely less on prototypic facial expressions than is often theoretically assumed.