AbstractLanguage input is crucial for language learning, with child-directed speech being a strong predictor of language development. Yet, in many non-industrialized rural societies, children are less exposed to this type of input. Instead, children encounter frequent child-surrounding speech from third-party interactions. Little is known about whether and how children learn language from this type of input. By analyzing naturalistic data from children growing up in the Shipibo-Konibo community in the Peruvian Amazon, we demonstrate that despite a high prevalence of child-surrounding input, child-directed input best predicts children’s production patterns defined as unigrams. We provide first evidence for remarkable similarities between child-surrounding speech and children’s own speech patterns. In addition, we demonstrate that a specific type of input best predicts children’s production frequencies across the domains of surrounding and directed input: speech from other children. Together, these findings expand our perspective beyond dyadic adult-child interactions, supporting the view that child-surrounding speech and especially speech from other children provide important learning opportunities.