The present study examines potential age and microparametric effects in childhood bilinguals (currently adults) in an understudied language pairing, Polish-Spanish. Specifically, a Spanish group (N = 28) and a Sequential child bilingual (N = 22) and a Simultaneous bilingual (N = 8) group living in Misiones, Argentina, completed three experimental tasks assessing their knowledge of the syntactic and syntax-semantic distribution of adjectives. Results show that, despite several semantic differences related to adjective position, both experimental groups demonstrate knowledge of interpretive constraints that fall out from underlying Spanish syntax. Differences predicted as a result of crosslinguistic influence were not evidenced, yet, contrary to Polish and Spanish, the experimental groups accepted ungrammatical postnominal intensional adjectives significantly more than Spanish speakers.