This study investigated the acquisition of demonstratives (e.g., "this/that," "here/there") by 45 children (1;0 - 4;11) learning Ticuna, an Indigenous Amazonian language with an unusually complex demonstrative system. I analyzed 89 10-minute samples from video recordings of child-caregiver interaction, examining how often children and caregivers produced each demonstrative type, as well as relationships among children's age, children's demonstrative production, and caregivers' production. Caregivers' demonstrative production displayed few relationships with children's age or production. Children produced speaker-proximal and speaker-distal demonstratives ("this near me, that far from me") earlier in developmental time than addressee-proximal demonstratives ("that near you"), and nominal ("this/that") demonstratives earlier than locative ("here/there") ones. Compared to caregivers, children overused speaker-proximal demonstratives, but used other demonstrative types with adult-like frequency beginning at 2;0. These results support the view that cognitive biases toward egocentric, proximal, and semantically simpler items substantially influence children's acquisition of demonstratives.