Four-year-old (n = 20) and five-year-old (n = 22) bilingual children were tested twice in six months on Armenian (minority language) and English (majority language) picture identification and picture naming tasks to examine receptive and expressive vocabulary growth in both languages. Parental education, Armenian/English language exposure, and nonverbal cognitive ability were also measured as potential predictors of vocabulary. Children showed growth over time in all four vocabulary tasks. However, less growth was observed in Armenian expressive task than in others, which indicated a preference to use English. Armenian language exposure was the unique predictor of Armenian picture identification and picture naming, whereas English language exposure was the unique predictor of English picture identification.