There is preliminary evidence that infant siblings of children with Autism Spectrum Disorder (ASD) have an atypical pattern of cry, characterized by higher fundamental frequency and increased dysphonation. This prospective study collected multiple cry samples of 12-month old siblings of children with ASD (n = 22, "high-risk" group) and…

Fragmented sleep is common in infancy. Although night awakening is known to decrease with age, in some infants night awakening is more persistent and continues into older ages. However, the influence of fragmented sleep on development is poorly known. In the present study, the longitudinal relationship between fragmented sleep and psychomotor…

This study examined whether a novel parent-report questionnaire, the Autism Parent Screen for Infants, could differentiate infants subsequently diagnosed with autism spectrum disorder from a high-risk cohort (siblings of children diagnosed with autism spectrum disorder (n = 66)) from high-risk and low-risk comparison infants (no family history of…

This paper presents research findings on differences in the social and cognitive behavior of first born and only children at 3, 12, and 24 months of age as observed at home and in a free play laboratory setting. The sample consisted of 21 only children (children who did not acquire a sibling for at least the first 48 months of life) and 35 first…

Investigated effects of older siblings on imitation by 12-, 15-, and 18-month-olds. Found that all age groups acquired one to two new behaviors per day through imitation. Older infants imitated more multi-step sequences and substituted more objects during reenactment than younger. Compared to infants without siblings, infants with siblings…