Aims and objectives: This study examines multiple associations between language domains in bilingual children with a focus on phonology. Previous studies indicate within- but not cross-language associations between vocabulary and grammar in bilingual children. We investigate whether the relation between phonology and other language domains differs from the one reported between vocabulary and grammar. Methodology: Canadian French-English bilingual children ( n = 31), aged 31 months, participated in 2 free-play sessions, from which lexical, grammatical and phonological information was extracted. The children's parents completed the MacArthur-Bates Communicative Developmental Inventories and its Canadian French adaptation providing additional information on vocabulary and grammar in each of the children's languages. They also completed a questionnaire on their children's exposure to French and English. Data analysis: Within and cross-language relations between phonology, vocabulary and grammar were investigated using correlational analyses and mixed logistic regression. Findings: Correlational analyses did not reveal significant cross-language relations between phonology, vocabulary and grammar. However, mixed logistic regression, which controlled for language exposure effects, indicated that phonology was influenced by vocabulary and grammar both within and across languages. Originality: This study is one of the first to study cross-domain relations involving phonology in young bilingual children. Implications: Overall, the findings suggest that phonology displays a pattern of relations that is different from other language domains engendering between-language effects due to a language-general component.