This much-awaited companion to Meaningful Differences reveals how children grow from babbling babies into social speakers. Based on unparalleled data from 2 1/2 years of observing 1- and 2-year-old children learning to talk in their own homes, this book charts the month-by-month growth of the children's vocabulary, utterances, and use of grammatical structures. Data expose the intricacies of how daily child-parent social interactions govern children's language and social development. The compelling narrative highlights reliability-tested research findings and is supplemented with transcripts and a list of more than 2,000 words of children's expressive vocabulary from 11 to 36 months of age.