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Before a child can speak (and the word 'infant' means 'one without speech'), the cooing of the young baby has pitch,
intonation, and cadence. Babbling is a form of tone and staccato rhythm, both of which are key elements of music and language.

Babies will imitate the timbre and cadences of adult speech before they learn to talk, as if they are practicing the melody of a song for which they do not yet have the words.

This is the vocal equivalent of building a library of sounds from which a vocabulary of language will be constructed.

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