Older Sibling Research Articles

Adaptive language strategies of an older sibling in bilingual German-Russian acquisition: A case study

Abstract In the beginning stages of language acquisition, children primarily learn language from their parents or main caregivers. Studies have shown that adults use a specific way of speaking when talking to young children, called child-directed speech (CDS). This type of speech has distinct characteristics across different aspects of language. Additionally, older siblings also communicate with their younger brothers and sisters. Studies suggest that even three- and four-year-olds change how they talk when interacting with younger children, like their siblings. Studies have shown that children’s speech patterns resemble those of adults, whether they grow up in monolingual or bilingual environments. However, research on bilingual language acquisition often focuses on how siblings influence the language development of younger children. In this study, we explore how children adapt their language in bilingual settings and focus on the older sibling. Specifically, we compare the speech of an older sibling, who speaks both German and Russian, when talking to their younger sibling and when talking to their parents. The study revealed the following: The girl demonstrated linguistic adaptations typical of child-directed speech in both Russian and German when interacting with her younger brother. However, these adaptations were not consistent across all linguistic categories analyzed, revealing some differences between the two languages. Notably, Katharina did not exhibit more child-directed speech features in one language over the other. Adaptive behavior was present in both Russian and German in categories such as MLU, MLU5, question constructions, and imperatives. In Russian, adaptation was also evident in coordinate constructions but not subordinate constructions, while the opposite pattern was observed in German.

“My brother teaches me everything”: Sibling mediation of young Israeli children’s media use

ABSTRACT This study sheds light on sibling mediation of young children’s media use, focusing on older brothers and sisters as significant mediators in imparting preferences, skills, and norms of media use in early childhood. The sample included 20 families with two or three children, one of whom was four to seven years of age and had at least one older sibling. In each family, in-depth interviews were conducted with the mothers, younger children, and with the older siblings. The findings indicated that older siblings served as playmates, digital mentors, parental proxies, and shields. These roles were crucial in their younger siblings’ media experiences, and much more significant than were the mediating roles of the parents, especially regarding the use of digital media.

Diverse phenotypes and fertility outcomes of patients with androgen insensitivity syndrome in a Chinese family harboring identical AR gene variant

BackgroundAndrogen insensitivity syndrome (AIS) is a rare genetic disorder characterized by resistance to androgens, mainly due to mutations in the androgen receptor (AR) gene. It can manifest as complete AIS, partial AIS and mild AIS. While there have been studies linking specific AR gene mutations to AIS phenotypes, different clinical AIS phenotypes are also reported in patients with the same AR gene mutation. So far, the precise correlations between phenotypes and genotypes remain incompletely understood.MethodsWe conducted a thorough investigation involving four patients diagnosed with different types of AIS from a single Chinese family. Clinical manifestations, laboratory examinations, and fertility outcomes were well-documented. Furthermore, we performed genetic sequencing to detect possible pathogenetic variants.ResultsWhole exome sequencing identified a hemizygous missense variant (c.2263T > C; p.Phe755Leu) of AR gene in all four affected patients with different degrees of undermasculinisation and heterogeneous spermatogenesis. The proband, diagnosed with partial AIS, opted for treatment with donated sperm due to non-obstructive azoospermia, while their older sibling, diagnosed with complete AIS, was raised as a girl. His two maternal uncles were both diagnosed with mild AIS, the older uncle fathered two girls naturally, whereas the younger uncle utilized assisted reproductive technology to conceive a boy because of severe oligoasthenozoospermia.ConclusionOur study first identified the same AR variant (c.2263T > C;p.Phe755Leu) in four affected patients displaying highly diverse phenotypes of AIS and fertility outcomes, thereby significantly expanding the phenotypic spectrum of AIS. Notably, we presented a clear insight into different fertility outcomes of AIS patients with identical AR (c.2263T > C;p.Phe755Leu) variant, which provided reliable evidence that males harboring this variant may obtain biological offspring naturally or in combination with assisted reproductive technology. Furthermore, our study underscored the potential role of androgen concentration in shaping the phenotypic diversity of AIS, warranting further investigation.

Cultivating the imagination: Caregiver input during pretend play with toddlers at elevated likelihood for autism.

Toddlers with autism spectrum disorder (ASD) may exhibit less pretend play than their neurotypical counterparts. Previous research suggests that caregivers' input during play influences children's play behavior, and children's behavior may in turn prompt caregivers of differently developing children to talk about play in different ways. Caregiver input about pretend play during toy play at home was examined at 18- and 36-months in toddlers with an older sibling with ASD, who are at elevated likelihood (EL) for ASD (n = 40), and toddlers with typical likelihood (TL) for ASD (n = 12). EL toddlers were classified into three outcome groups: EL-ASD (n = 10), EL-no diagnosis (EL-ND; n = 14), or EL-language delays (EL-LD, n = 16). Caregiver utterances were categorized according to the types of pretend and non-pretend play suggested (e.g., pretending with inanimate objects vs. using objects for their intended function). Pretend utterances were further categorized as related or unrelated to the child's own actions. All caregivers produced proportionately more utterances about complex types of pretend play over time. At 36 months, caregivers of autistic toddlers produced proportionately fewer pretend play utterances, and proportionately fewer pretend play utterances were related to EL-ASD toddlers' actions compared to their neurotypical peers. These findings highlight bidirectional effects between caregivers and toddlers during play. While EL-ASD toddlers may provide less frequent opportunities for caregivers to talk about complex types of pretend play, the current study highlights caregivers' high levels of attunement to their toddlers' play skills.

Risk factors associated with the incidence of asthma among adolescents in Ukraine

Background. Asthma is a common disease among children and adolescents. The purpose of this study was to describe the detailed characteristics of adolescents with asthma, identify risk factors associated with the development of asthma and to evaluate medical care for patients with asthma. Materials and methods. Asthma patients (n = 80) aged 12 to 18 years from the Allergology Department of the Kyiv City Children’s Clinical Hospital 2, the clinical base of the Department of Pediatrics 2 of the Bogomolets National Medical University, were included in the study. The control group consisted of 120 children without asthma. In the group of interviewed children, asthma was diagnosed based on clinical data and objective measurement of lung function. All children underwent spirometry and skin prick test with aeroallergens. During the clinical examination, weight and height were measured, and body mass index was calculated. The survey was conducted by a research doctor using a Google form. Results. Parents of 80 children with asthma were involved in our survey between September 2023 and May 2024. Asthma occurred more often in boys than in girls: odds ratio (OR) = 7.3 (95% confidence interval (CI) 3.84–14.16, P < 0.0001). 31.25 % respondents reported a history of atopic dermatitis, 26.25 % had atopic dermatitis at the time of the study. Food allergy was detected in 25 % children. 48.75 % children had concomitant allergic rhinitis, of which 33.75 % had seasonal, 15 % had perennial. We found that children living in the city had asthma more often: OR = 7.3 (95% CI 3.26–16.62, P < 0.0001). Having an older sibling was associated with a lower risk of asthma: OR = 3.6 (95% CI 1.86–6.92, P < 0.0001). Also, we found that cat owners were significantly more likely not to have asthma: OR = 7.7 (95% CI 3.96–14.99, P < 0.0001). Such data are most likely related to the refusal to own a cat due to the prevalence of cat allergy among children with asthma or at risk of cat allergy. We have not found a statistically significant difference in the group of children with asthma and in the control group in relation to the exposure to tobacco smoke in the atmosphere (passive smoking): OR = 1.4 (95% CI 0.79–2.59, P > 0.05). Conclusions. Treatment of allergies and atopic conditions should be considered an important component of asthma treatment, which may affect the frequency and severity of the disease. In adolescents and adults, smoking cessation, in particular, as a factor in the impact of passive smoking on a sick child can also significantly reduce the number of hospitalizations. Confirming the diagnosis of asthma, demonstrating good inhaler technique, and emphasizing adherence to preventive therapies such as inhaled glucocorticosteroids can improve asthma control and reduce overreliance on short-acting bronchodilators.

Fostering Dialogic Reading Through Older Siblings in Immigrant Latino Families: A Pilot Study

To promote children’s language development through designs that consider familial contexts, the authors explored the effectiveness of a dialogic reading intervention customized for older siblings in immigrant Latino families. The dialogic reading intervention, developed with components of training, modeling, and coaching, systematically supported older siblings’ dialogic reading use while reading with their younger siblings. Using the CROWD mnemonic, older siblings were taught to use a range of dialogic reading prompts, thereby nurturing diverse forms of engagement during shared interactive book reading (SIBR) sessions. Moreover, older siblings were taught the PEER mnemonic to enhance their ability to respond to their younger siblings’ input in manners conducive to promoting the latter’s language development. Effects of the intervention program on three older siblings’ (1) prompting and (2) responsiveness during SIBR were assessed using a multiple-baseline across participants design. Results indicate that two out of three older siblings increased prompt frequency and demonstrated improved responsiveness after receiving coaching and modeling support. Challenges faced by one older sibling are discussed, potentially attributed to individual language and literacy difficulties. Results tentatively indicate that older siblings have the capacity to acquire and apply dialogic reading skills if given appropriate instruction and support. These results illuminate opportunities to enhance SIBR techniques among siblings, underscoring the significant role older siblings in immigrant Latino families can play in providing enriched language input during SIBR.

Can combining existing behavioral tools improve identification of infants at elevated likelihood of autism in the first year of life?

Many families have concerns about their infants' development in the first year of life. Current screeners cannot tell whether these differences might be related to autism, developmental delays, or likely to resolve on their own. As a result, many families are told to "wait and see." In this study, we looked at whether combining multiple behavior measures can improve prediction of outcomes in toddlerhood. This could help to provide families with more information about the significance of early behavioral differences. We assessed 256 infants with an older autistic sibling at 6, 9, and 12 months. We created three markers of behavioral differences at these ages. We looked at whether infants who had two or more markers were more likely to be on the autism spectrum or have other developmental differences than to have typically developing outcomes at 36 months. We found that very few infants had more than one marker at any age. However, infants who showed two or more markers were more likely to be on the spectrum or have other developmental differences at 36 months than infants who showed only one marker. These findings suggest that when behavioral differences are present on multiple measures, there is no need to wait and see before referring for services.

Evaluation of early treatment with intravenous idursulfase and intrathecal idursulfase-IT on cognitive function in siblings with neuronopathic mucopolysaccharidosis II.

Mucopolysaccharidosis II (MPS II; Hunter syndrome; OMIM 309900) is a rare, X-linked, heterogeneous lysosomal storage disease. Approximately two-thirds of patients develop cognitive impairment, which is difficult to assess in clinical trials, partly owing to the variable nature of cognitive impairment. Analyzing data from siblings can help to minimize this heterogeneity. We report analyses of cognitive function from siblings with MPS II enrolled in clinical trials: a natural history study (NCT01822184), a randomized, open-label, phase 2/3 study of intravenous (IV) idursulfase with or without intrathecal idursulfase (idursulfase-IT; NCT02055118), and its extension (NCT2412787). Cognitive function was assessed using Differential Abilities Scales, Second Edition General Conceptual Ability (DAS-II GCA) scores; Bayley Scales of Infant and Toddler Development, Third Edition; and Vineland Adaptive Behavior Scales, Second Edition Adaptive Behavior Composite (VABS-II ABC). Seven sets of siblings (six pairs and one set of three) were included. All patients received IV idursulfase and 10 received subsequent idursulfase-IT. Younger siblings initiated IV idursulfase at an earlier age than their older sibling(s) in six of the sets; the younger sibling started treatment before 1 year of age in three sets. Monthly idursulfase-IT was generally associated with a stabilization of cognitive function: DAS-II GCA and VABS-II ABC scores were higher at age-matched assessments in the majority of those who either received idursulfase-IT earlier than their sibling or who received idursulfase-IT versus no idursulfase-IT. These data suggest that early initiation of intrathecal enzyme replacement therapy may stabilize or slow cognitive decline in some patients with neuronopathic MPS II.

Rapid lipid-lowering response in two cases of autosomal recessive hypercholesterolemia

BackgroundAutosomal recessive hypercholesterolemia (ARH) is an ultrarare dyslipidemia caused by variants in the LDLRAP1 gene. Clinically, this condition is indistinguishable from other homozygous familial hypercholesterolemia (HoFH). CaseWe present the cases of two siblings diagnosed with ARH caused by LDLRAP1 gene c.617-14C>A splicing homozygous variant. Over a five-year treatment period, the older sibling experienced an 81 % reduction in low-density lipoprotein cholesterol (LDL-C) levels with the maximal dose of pitavastatin plus ezetimibe, while the younger sibling achieved a 75 % reduction. After three sessions, the older brother no longer required LDL apheresis, and the sibling never had LDL apheresis. ConclusionOur findings demonstrate a rapid and significant response to lipid-lowering therapy (LLT) in patients with ARH caused by c.617-14C>A splicing VUS variant, a condition that mimics HoFH at diagnosis. Long-term follow-up studies in large pediatric cohorts of ARH patients treated with pitavastatin plus ezetimibe from childhood are necessary to better define the risk of cardiovascular disease (CVD) development.

Our Journey from Individual Efforts to Nationwide Support: Implementing Newborn Screening for Spinal Muscular Atrophy in Serbia.

Innovative treatments for spinal muscular atrophy (SMA) yield the utmost advantages only within the presymptomatic phase, underlining the significance of newborn screening (NBS). We aimed to establish statewide NBS for SMA in Serbia. Our stepwise implementation process involved technical validation of a screening assay, collaboration with patient organizations and medical professionals, a feasibility study, and negotiation with public health representatives. Over 12,000 newborns were tested during the 17-month feasibility study, revealing two unrelated SMA infants and one older sibling. All three children received therapeutic interventions during the presymptomatic phase and have shown no signs of SMA. No false-negative results were found among the negative test results. As frontrunners in this field in Serbia, we established screening and diagnostic algorithms and follow-up protocols and raised awareness among stakeholders about the importance of early disease detection, leading to the incorporation of NBS for SMA into the national program on 15 September 2023. Since then, 54,393 newborns have been tested, identifying six SMA cases and enabling timely treatment. Our study demonstrates that effective collaborations between academia, non-profit organizations, and industry are crucial in bringing innovative healthcare initiatives to fruition, and highlights the potential of NBS to revolutionize healthcare outcomes for presymptomatic SMA infants and their families.

Prevalence of Developmental, Psychiatric, and Neurologic Conditions in Older Siblings of Children with and without Autism Spectrum Disorder: Study to Explore Early Development.

This study evaluated developmental, psychiatric, and neurologic conditions among older siblings of children with and without autism spectrum disorder (ASD) to understand the extent of familial clustering of these diagnoses. Using data from the Study to Explore Early Development, a large multi-site case-control study, the analyses included 2,963 children aged 2-5 years with ASD, other developmental disabilities (DD group), and a population-based control group (POP). Percentages of index children with older siblings with select developmental, psychiatric, and neurologic conditions were estimated and compared across index child study groups using chi-square tests and multivariable modified Poisson regression. In adjusted analyses, children in the ASD group were significantly more likely than children in the POP group to have one or more older siblings with ASD, developmental delay, attention-deficit/hyperactivity disorder, intellectual disability, sensory integration disorder (SID), speech/language delays, or a psychiatric diagnosis (adjusted prevalence ratio [aPR] range: 1.4-3.7). Children in the DD group were significantly more likely than children in the POP group to have an older sibling with most of the aforementioned conditions, except for intellectual disability and psychiatric diagnosis (aPR range: 1.4-2.2). Children in the ASD group were significantly more likely than children in the DD group to have one or more older siblings with ASD, developmental delay, SID, or a psychiatric diagnosis (aPR range: 1.4-1.9). These findings suggest that developmental disorders cluster in families. Increased monitoring and screening for ASD and other DDs may be warranted when an older sibling has a DD diagnosis or symptoms.

Familial Recurrence of Autism: Updates From the Baby Siblings Research Consortium.

Autism spectrum disorder (ASD) is estimated to be ∼10 times higher in children with versus without an autistic sibling in population-based studies. Prospective studies of infant siblings have revealed even higher familial recurrence rates. In the current prospective longitudinal study, we provide updated estimates of familial ASD recurrence using a multinational database of infants with older autistic siblings. Data were collated across 18 sites of the Baby Siblings Research Consortium, an international network studying the earliest manifestations of ASD. A total of 1605 infants with an older autistic sibling were followed from early in life to 3 years, when they were classified as ASD or non-ASD. Hierarchical generalized linear modeling, with site as a random effect, was used to examine predictors of recurrence in families and calculate likelihood ratios. A total of 20.2% of siblings developed ASD, which is not significantly higher than the previously reported rate of 18.7%. Male infant sex and >1 older affected sibling were significant predictors of familial recurrence. Proband sex also influenced recurrence rates, with siblings of female probands significantly more likely to develop ASD than siblings of male probands. Race and maternal education were also associated with recurrence in families. The familial recurrence rate of ASD, as measured in infant sibling studies, has not changed appreciably since previous estimates were made in 2011. Younger siblings of autistic children, particularly those who are male, have an affected female sibling, multiple affected siblings, or are impacted by social inequities, should be closely monitored and promptly referred for diagnostic evaluation.

An early-life challenge: becoming an older sibling in wild mandrills.

In monotocous mammals, most individuals experience the birth of a younger sibling. This period may induce losses in maternal care and can be physiologically, energetically and emotionally challenging for the older sibling, yet has rarely been studied in wild primates. We used behavioural data collected from a natural population of mandrills to investigate changes in maternal care and mother-juvenile relationship throughout the transition to siblinghood (TTS), by comparing juveniles who recently experienced the birth of a younger sibling, to juveniles who did not. We found that the TTS was associated with an abrupt cessation of the weaning process for the juvenile, and to a decrease in maternal affiliation. Juveniles' reactions were sex-specific, as males associated less with their mother, while females tended to groom their mother more often after the birth of their sibling. Despite the substantial loss of maternal care, juveniles did not show an increase in conflict or anxiety-related behaviours. This study contributes to explain why short interbirth intervals often pose a risk to juveniles' survival in monotocous primates. Our results contrast existing studies and further highlight the importance of examining the TTS in species and populations with various life histories and ecologies.

Mid-childhood autism sibling recurrence in infants with a family history of autism.

Autism sibling recurrence in prospective infant family history studies is ~20% at 3 years but systematic follow-up to mid-childhood is rare. In population and clinical cohorts autism is not recognized in some children until school-age or later. One hundred and fifty-nine infants with an older sibling with autism underwent research diagnostic assessments at 3 years and mid-childhood (6 to 12 years (mean 9)). We report the autism sibling recurrence rate in mid-childhood and compare developmental and behavioral profiles at mid-childhood and 3 years in those with earlier versus later recognized autism, and those who had, or had not, received a community autism diagnosis. The autism recurrence rate in this sample in mid-childhood was 37.1%, 95% CI [29.9%, 44.9%] and higher in boys than girls. Around half of those diagnosed with autism in mid-childhood had not received a diagnosis at 3 years. Later, diagnosis was more common in girls than boys. While some had sub-threshold symptoms at 3, in others late diagnosis followed a largely typical early presentation. Sibling recurrence based on community clinical diagnosis was 24.5%, 95% CI [18.4%, 31.9%]. Those who also had a community diagnosis tended to be older, have lower adaptive function and higher autism and inattention symptoms. Notwithstanding limitations of a single site study, modest sample size and limits to generalisability, autism sibling recurrence in family history infants may be higher in mid-childhood than in studies reporting diagnostic outcome at 3 years. Findings have implications for families and clinical services, and for prospective family history studies.

The Playhouse Effect: John Webster, Deixis and Story-Telling in the Theatres of Jacobean London

The recent (2014) inauguration of the Sam Wanamaker Playhouse, a reconstruction of an archetypal Jacobean indoor playhouse, on London’s Southbank, has led students and scholars of early modern theatre once again to focus attention on original playhouse performances, just as they did when its older sibling Shakespeare’s Globe opened its doors in 1996. The earlier assumption that the differences between open-air amphitheatres and indoor playhouses conditioned the way plays were written and acted is now enjoying a new lease on life, and yet there has been little research conducted in order to substantiate this otherwise perfectly logical intuition. Drawing on the insights of drama theorist Manfred Pfister as well as the linguistic concept of deixis, this article compares the language and plotting of three plays by the Jacobean playwright John Webster: The White Devil, The Duchess of Malfi and The Devil’s Law Case. Each play was first staged under significantly different circumstances within the theatrical landscape of Jacobean London, which makes them a singularly illustrative case study of how an early modern English dramatist adapted his style in order to meet the demands of the city’s diverse performance conditions.

Familial Factors Impacting First-Generation College Students’ Adjustment: The Compensatory Role of Older Siblings With College Experience

ABSTRACT Previous studies show that familial support promotes first-generation college students’ (FGCS) academic and social adjustment, but limited research has examined the impact of having older siblings who attended college. In this longitudinal study, 169 FGCS completed online questionnaires assessing academic and psychosocial factors at the beginning and end of their first year. Controlling for potential confounds in multivariate regressions, parent support was positively associated with subjective indicators of academic and social adjustment. Having older sibling(s) with college experience was positively associated with social adjustment when parent support was low, demonstrating an interaction effect. I discuss practice implications and future directions.

The effect of a peer’s teen pregnancy on sexual behavior

We examine whether a friend or older sibling’s teen pregnancy impacts one’s own sexual behavior. Employing an event study design and rich retrospective data on sexual activity, we find that those who observe a peer’s teen pregnancy change sexual behavior after the pregnancy ends to put themselves at lower risk of their own teen pregnancy; specifically, they are less likely to have unprotected sex and have fewer sexual partners in the year following the end of the teen pregnancy. We find that females are more likely to change their sexual behavior compared to males, and the effects are primarily driven by peer live births, as opposed to other pregnancies. Ultimately, we find a slight decline in the likelihood of one’s own teen pregnancy, though estimates are noisy. Our work suggests that education campaigns that provide a realistic portrayal of teen parenthood may be an effective tool for impacting teen behavior.

Atypical functional connectivity between the amygdala and visual, salience regions in infants with genetic liability for autism.

The amygdala undergoes a period of overgrowth in the first year of life, resulting in enlarged volume by 12months in infants later diagnosed with ASD. The overgrowth of the amygdala may have functional consequences during infancy. We investigated whether amygdala connectivity differs in 12-month-olds at high likelihood (HL) for ASD (defined by having an older sibling with autism), compared to those at low likelihood (LL). We examined seed-based connectivity of left and right amygdalae, hypothesizing that the HL and LL groups would differ in amygdala connectivity, especially with the visual cortex, based on our prior reports demonstrating that components of visual circuitry develop atypically and are linked to genetic liability for autism. We found that HL infants exhibited weaker connectivity between the right amygdala and the left visual cortex, as well as between the left amygdala and the right anterior cingulate, with evidence that these patterns occur in distinct subgroups of the HL sample. Amygdala connectivity strength with the visual cortex was related to motor and communication abilities among HL infants. Findings indicate that aberrant functional connectivity between the amygdala and visual regions is apparent in infants with genetic liability for ASD and may have implications for early differences in adaptive behaviors.

Comparative efficacy of an early intervention “parent and me” program for infants showing signs of autism: The Baby JASPER model

Despite important advancements into the early detection of autism, there are still few empirically supported interventions for children under the age of two years who are showing early signs. Caregiver-mediated interventions have gained in popularity as a method for delivering support to the child and family. The current study builds on current work by enrolling a comparatively large cohort of infants (ages 12–22 months of age) displaying early signs of autism into a randomized controlled intervention program. Infants and parents received a group-based program using a standard early childhood curriculum. In addition, all families were randomly assigned to receive parent training in the form of either parent-mediated Joint Attention Symbolic Play Engagement and Regulation (JASPER) training or psychoeducation. Infants in both classrooms made substantial gains in social-communication, play, and cognition during a brief, 8-week period. All infants gained over an average of 10 points in DQ and increased in standardized measures of social-communication and play, with these gains maintaining at a 2-month follow-up visit. The classroom that also received JASPER increased in child initiated joint engagement and play level during dyadic interactions with their parents, while the classroom that received psychoeducation increased in joint attention during a standardized assessment delivered by an independent assessor. Infant familial risk for autism (older sibling with autism) also moderated the effect of treatment on child initiated joint engagement where infants in the JASPER classroom without familial risk made the most gains from baseline to exit of the program. This study highlights the promise of intervening at the earliest stages to promote positive outcomes for children and families.

Investigating Parental Observations of Early Autism Development in Simplex and Multiplex Families.

Past research has highlighted the importance of early identification of developmental differences to improve targeted access to early interventions or supports. As such, it is of particular importance in the context of children at elevated likelihood of autism (such as where an older sibling has a diagnosis of autism), to better understand when and which early concerns are important as predictors of which children will benefit from pre-diagnostic supports. This study explored the number and frequency of retrospective parent reported concerns within the first year of life for children diagnosed with autism, both those who had an older sibling diagnosed with autism and those who did not, as well as for undiagnosed siblings. We found that at both 0-6 and 7-12 months, the only factor related to the presence or absence of early parent reported concerns was child diagnostic status, with the presence of reported early concerns more likely for children with a diagnosis of autism. These findings suggest that for children at elevated likelihood of autism, parents' concerns are driven primarily by developmental differences, with child's birth order and sibling diagnostic status not impacting on parent early concerns.