This study examines Lithuanian children's acquisition of gender agreement using an elicited production task. Lithuanian is a richly inflected Baltic language, with two genders and seven cases. Younger (N=24, mean 3;1, 2;5–3;8) and older (N=24, mean 6;3, 5;6–6;9) children were shown pictures of animals and asked to describe them after hearing the animal's name. Animal names differed with respect to familiarity (novel vs. familiar), derivational status (diminutive vs. simplex) and gender (masculine vs. feminine). Analyses of gender-agreement errors based on adjective and pronoun usage indicated that younger children made more errors than older children, with errors more prevalent for novel animal names. For novel animals, and for feminine nouns, children produced fewer errors with nouns introduced in diminutive form. These results complement findings from several Slavic languages (Russian, Serbian and Polish) that diminutives constitute a salient cluster of word forms that may provide an entry point for the child's acquisition of noun morphology.