Phonological awareness is critical for early reading acquisition across alphabetic as well as non-alphabetic languages. The grain size of phonological awareness varies with oral language structure and written orthography across languages. Phonological awareness' grain size and contribution to reading for simultaneous biliterate children is currently unknown. In this study, we examine syllable, rime and phoneme level awareness for bilingual children with differences in structure of their known languages in order to investigate any potential cross-language effects of their ethnic language on English reading. For 612 Chinese and English, Malay and English, and Tamil and English speakers in kindergarten, different patterns emerged across the language groups with regard to the grain size of phonological awareness over a 2-year period. The patterns of phonological awareness levels in predicting early English reading skills also differed amongst these bilingual language groups. The role of vocabulary in the relation between phonological awareness and reading was not consistent, showing small moderating and mediating effects only in some instances.