Theories concerning the development of phonological awareness place special emphasis on lexical and orthographic knowledge. Given the large degree of variability in preschool classrooms that house Spanish-speaking English language learners (ELL), this study controlled for classroom effects by removing classroom means and covariances based on 158 children from 40 classrooms. Path analyses of the child-level covariance matrices tested the extent to which vocabulary and letter knowledge in each language predicted growth in English and Spanish phonological awareness of 130 preschool-age, Spanish-speaking ELLs. Results supported cross-linguistic effects of prior phonological awareness and Spanish vocabulary in the development of bilingual phonological awareness. Implications for theory, instruction, and research methods are discussed. (Contains 5 tables and 1 figure.)