Previous scholarship on childish language in ancient Greece has focussed narrowly on hypocoristics, particularly their phonology. This paper focusses on three much broader questions: (i) Which juvenile linguistic features might Greek children have exhibited at different ages? (ii) Which of these are represented in ancient texts? (iii) Which texts explore child language in unusual ways? I base my argument on pre-Hellenistic sources, supplemented by many later ones. In section 1 I discuss 'external' evidence, namely the possibility of extrapolating results from contemporary developmental psycholinguistics to the situation in ancient Greece, and extant letters and compositions by youths. In section 2 I survey my findings about ancient awareness of child language acquisition under the following heads: pre-babbling and babbling; first words; phonology, articulation, and pronunciation; lexicon and semantics; word-accent; morphology and syntax; pragmatics. I then offer an explanation for why most ancient sources focus on phonology-articulation-pronunciation, hypocoristics, and three features of pragmatics. Finally, in section 3, I offer a close reading of a source which engages in an unusual way with child language - the Homeric Hymn to Hermes, 263f.