Mothers' speech to children of four different ages.

This study reports analyses, in terms of five different measures, of the speech on two standard tasks of 32 middle-class mothers to their children aged 1 1/2, 2 1/2, 4, and 6 years. Sex and birth order of child were not found to be related to mothers' speech. On four of the measures, both task and age of child had strongly significant effects. In general, with increasing age of child, mothers spoke more, in longer and grammatically more complex utterances, with greater diversity of vocabulary. The differences in speech addressed to 1 1/2-year-olds and that addressed to 2 1/2-year-olds were particularly marked.