Friendship is a fundamental part of being human. Understanding which cues indicate friendship and what friendship entails is critical for navigating the social world. We survey research on 3‐ to 6‐year‐old children’s friendship concepts, discussing both classic work from the 1970s and 1980s using interview methods, as well as current work using simpler experimental tasks. We focus on three core features of young children’s friendship concepts: (1) proximity, (2) prosocial interactions, and (3) similarity. For each, we discuss how recent findings extend and expand classic foundations. Importantly, we highlight that children’s knowledge develops earlier and is deeper than initially hypothesized, and how children’s abilities are supported by early social inferences in infancy. We examine the implications of young children’s friendship concepts and note exciting new avenues for future research.

中文翻译：

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紧记朋友：幼儿期的友谊概念的发展

友谊是人类的基本组成部分。了解哪些线索表示友谊，以及友谊意味着什么，对于导航社交世界至关重要。我们对3至6岁儿童的友谊概念进行了调查，讨论了使用访谈方法讨论的1970年代和1980年代的经典作品，以及使用较简单的实验任务进行的当前作品。我们关注幼儿友谊概念的三个核心特征：（1）亲近，（2）亲社会互动和（3）相似性。对于每一个，我们讨论最近的发现如何扩展和扩展经典基础。重要的是，我们强调儿童的知识比最初的假设发展得更早，更深入，并且婴儿期的早期社会推断如何支持儿童的能力。