Language onset and concomitant speech and language problems in subgroups of stutterers and their siblings.

Time of language onset and frequencies of speech and language problems were examined in stutterers and their nonstuttering siblings. These families were grouped according to six characteristics of the index stutterer: sex, recovery or persistence of stuttering, and positive or negative family history of stuttering. Stutterers and their nonstuttering same-sex siblings were found to be distributed identically in early, average, and late categories of language onset. Comparisons of six subgroups of stutterers and their respective nonstuttering siblings showed no significant differences in the number of their reported articulation problems. Stutterers who were reported to be late talkers did not differ from their nonstuttering siblings in the frequency of their articulation problems, but these two groups had significantly higher frequencies of articulation problems than did stutterers who were early or average talkers and their siblings.