Measures fathers' and mothers' linguistic involvement in the development of communication between young siblings--infants and toddlers. In a laboratory setting, 39 families, each with a mother, a father and two children, were videotaped in semistructured activities. Results suggest that fathers very actively direct sibling interactions, especially…

A comparison is presented of a mother's language to her Down Syndrome two-year-old and his normally developing twin. When interacting with the Down Syndrome twin, the mother used shorter mean length of utterance, greater type-token ratio, more confirmations, more verbal directives, fewer yes-no and true questions, and more directive questions.…