Studies of English and French show that children's first articles are more likely to appear when they can be prosodified as part of a disyllabic foot (cf. Gerken, 1996; Demuth & Tremblay, 2008). However, preliminary studies of Spanish suggest that children's first articles appear in larger prosodic structures, possibly due to the higher frequency of longer words. To assess this issue, this study examined longitudinal data from two Spanish 1- to 2-year-olds. As expected, both produced their early articles with monosyllabic and disyllabic nouns, rapidly expanding article use to trisyllabic nouns as well. The results suggest that the prosodic complexity of the lexicon plays an important role in the development of prosodic structure, providing the context for early prosodic licensing of grammatical morphemes.