Even advanced Spanish speakers of second language Englishtend to confuse the pronouns ‘he’ and ‘she’, often withouteven noticing their mistake (Lahoz, 1991). A study by Antón-Méndez (2010) has indicated that a possible reason for this er-ror is the fact that Spanish is a pro-drop language. In order totest this hypothesis, we used an extension of Dual-path (Chang,2002), a computational cognitive model of sentence produc-tion, to simulate two models of bilingual speech production ofsecond language English. One model had Spanish (ES) as anative language, whereas the other learned a Spanish-like lan-guage that used the pronoun at all times (non-pro-drop Span-ish, NPD_ES). When tested on L2 English sentences, the bilin-gual pro-drop Spanish model produced significantly more gen-der pronoun errors, confirming that pronoun dropping couldindeed be responsible for the gender confusion in natural lan-guage use as well.