Language develops through the communication with different persons in different situations. The persons with whom the child communicates in particular language are the ones who create his social network for that language.Ties in social networks can be weak or strong and rare od dense. The persons with whom the child communicates frequently and intensly create dense and strong ties in social network for particular language, and this ties are proven to be important for language development. Studies of bilingual communities have shown that social network analysis can predict the direction of language development, but social networks are still the subject of research and efforts are being made to determine which part (number of ties, type of ties) has the greatest impact on language development. That was the theme of this research, too. The study included 20 bilingual children from Istria, of whom 15 boys and 5 girls, aged 5;11 to 6;08 years. All the children are acquiring Croatian and Italian language and attend Italian kindergarten. The spoken language sample was collected using the Multilingual Assessment Instrument for Narratives (MAIN; Gagarina i sur., 2012- Croatian version; Gagarina i sur., 2015). Audio files were trancsribed and coded in CLAN (MacWhiney, 2000). The aim of this research was to determine whether bilingual development is related to the structure of social network (number of ties, type of ties) for each language. Language development was assessed by the analysis of spoken language samples, using five measures: total number of words, number of different words, type-token ratio, moving average type-token ratio and mean length of utterance. The results on the measure of syntactic complexity and on one measure of lexical diversity showed better language proficiency in Croatian within the group. Contrary to the expectations, the number of domains of language use did not prove to be statistically significantly correlated with scores on language measures in that particular language, and this raised a question for future research about the importance of each domain for language development. The number of strong and dense ties was found to be statistically significantly related to the scores on language measures in the Italian language only, in terms of the type-token ratio measure, indicating the importance of this ties for development of minority language vocabulary.