Two studies (N = 68, ages 2;0–3;11; N = 80, ages 2;6–4;11) explore the idea that, rather than starting with a separate mental category for each discrete emotion, children start with two broad categories (positive and negative) and then differentiate within each until adult-like categories form. Children generated emotion labels for (a) facial expressions or (b) stories about an emotion’s cause and consequence. Emotions included were happiness, anger, fear, sadness, and disgust. Both conditions yielded the predicted pattern of differentiation. These studies of younger children found the face more powerful in eliciting correct emotion labels than had prior research, which typically relied on older preschoolers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)