This study examined whether type of early language experience provides advantages to heritage speakers over second language (L2) learners with morphology, and investigated knowledge of gender agreement and its interaction with diminutive formation. Diminutives are a hallmark of Child Directed Speech in early language development and a highly productive morphological mechanism that facilitates the acquisition of declensional noun endings in many languages (Savickiene ̇ and Dressler, 2007). In Spanish, diminutives regularize gender marking in nouns with a non-canonical ending. Twenty-four Spanish native speakers, 29 heritage speakers and 37 L2 learners with intermediate to advanced proficiency completed two picture-naming tasks and an elicited production task. Results showed that the heritage speakers were more accurate than the L2 learners with gender agreement in general, and with non-canonical ending nouns in particular. This study confirms that early language experience and the type of input received confer some advantages to heritage speakers over L2 learners with early-acquired aspects of language, especially in oral production.