This research investigates the effectiveness of using a child’s first language (L1), specifically Spanish, with Audio Prompting (AP) delivered via a tablet computer by monolingual English-speaking clinicians to enhance vocabulary growth in the L1 and second language (L2) of children who are English Learners (ELs). Outcomes of vocabulary instruction for Spanish-speaking preschoolers assigned to one of three groups: (a) Spanish–English instruction ( n = 14) with Spanish delivered through AP, (b) English-only instruction ( n = 14), and (c) control group ( n = 15) indicates that both Spanish–English instruction and English-only instruction may result in greater gains in English naming when compared with no instruction. Importantly, Spanish–English instruction may produce greater gains in English definition as well as Spanish naming and definition when compared with no instruction, with outcomes maintained post instruction. AP can be useful to increase L1 and L2 vocabulary and definition in ELs, once monolingual English-speaking speech-language pathologist is trained in the use of AP.