Encoding only-type exclusive focus in discourse involves complex computation and integration of knowledge from multiple linguistic domains. We present a comprehensive analysis of syntactic, semantic, prosodic, and discourse contextual features of 864 utterances with only and its Mandarin equivalents zhi(you) produced by Mandarin–English bilingual preschoolers and matched monolinguals (age 2–6, Study 1), and by Mandarin-speaking parents (Study 2), all sampled from naturalistic interactions. The results revealed largely target-like syntactic positioning and semantic association of only and zhi(you) in both languages in the bilinguals, with cross-linguistic influence between only and zhi. Interestingly, the bilingual children, like their Mandarin monolingual peers, employed longer duration but not raised mean pitch to shift the prosodic stress to the intended focus, although both acoustic features, in addition to positional and contextual cues, were instantiated in the focus utterances in the Mandarin parental input, suggesting prolonged development in focus-prosody mapping in children independent of bilingualism.