The present study examines variable realizations of Spanish word-initial voiced and voiceless dental stops in Spanish-English cognate pairs. Employing a variationist approach to naturalistic data, we report significantly decreased likelihood of reduced articulations of word-initial /d/ in cognates in spontaneous bilingual Puerto Rican discourse, and no such probabilistic effect for cognates in monolingual Spanish of the same speech community. Using experimentally controlled elicited data of Spanish word-initial /t/, we also find evidence of significant fine-grained effects of English on the articulations of Spanish cognates in the form of lengthened VOT for Spanish-English bilinguals. These results indicate that cross-language lexical connections affect phonetic categories in the speech production of Spanish-English bilinguals. It is proposed that both fine-grained and probabilistic effects of the phonology of one language on another can be explained within the Exemplar Model of Lexical Representation.