While there may be many similarities in the adaptation of family members to various chronic illnesses and disabilities, the distinct social deficits and difficulties associated with ASD suggest that the adaptation pathway and experience for this subset of families is unique. Having a family member with any illness or disability can be a challenge for the entire family system, but the unique combination of impairments in autism can place the family at an especially high risk for psychological difficulties (Dunn et al. 2001; Glasberg 2000; Morgan 1988). Compared to other developmental disabilities where a clear genetic cause can be detected (such as Down syndrome or Fragile X syndrome), ASD is an ambiguous and complex condition with an aetiology that is not yet fully understood. Families may find it more difficult to come to terms with a diagnosis given the polygenetic nature of the disorder and the uncertain risk they carry for expression or transmission (Bailey 2007). Additionally, the variability of cognitive ability across the full spectrum of ASDs contributes to parental and sibling confusion regarding diagnosis and prognosis. Research has shown that ambiguous disabilities are associated with poorer sibling outcomes than the presence of a sibling with a more concrete developmental disorder (Macks and Reeve 2007). Diagnostic ambiguity such as that inherent in a diagnosis of an ASD has also been shown to lead to lower levels of family harmony (Perry et al. 2004). This provides a further layer of challenge for families to make sense of and accept the child’s condition.

Another factor that affects the adaptation of the family to a diagnosis of autism is the unique social, behavioural and communicative deficits in these individuals that affect the family, and in turn the child’s relationship with other family members (Meadan et al. 2010). The child’s unusual patterns of behaviour, repetitive and restricted interests and routines and challenging behaviours can impact the whole family system and have a profound effect on the adaptation process. Given the greater complexity, unpredictability and inexplicability of autism over other developmental conditions, it has been shown that the family is at higher risk for poor psychological adjustment (Bebko et al. 1987; Morgan 1988; Rodrigue et al. 1993). Bebko et al. (1987) found that in comparison to families of children with other disabilities, families of children with autism experienced greater disruption of family functioning, more upset and disappointment about the child with the disability, and reported participating in fewer recreational activities and vocational opportunities due to the nature of their child’s condition.

A further complicating factor for family adaptation to children with a disability is that many exhibit challenging behaviours that can be unpredictable and difficult to manage, which can contribute to family stress. Given that behavioural difficulties are a core impairment in autism (McClintock et al. 2003), and that behavioural disturbances in children with autism are more complex and severe than in other developmental disorders (Eisenhower et al. 2005; McClintock et al. 2003; Morgan 1988; Noterdaeme et al. 2002), it is not surprising that this area brings particular challenges to families of children with this condition. In his research review, Bailey (2007) reported that most studies analysed showed that positive family adaptation is much more difficult to achieve when children exhibit a high rate of behaviour problems. There is considerable evidence that problematic behaviours in children with autism negatively impact parental wellbeing (Morgan 1988; Seltzer et al. 1997) and the sibling relationship (Greenberg et al. 1999; Orsmond and Seltzer 2007; Seltzer et al. 1997). The added burden of challenging behaviour makes adaptation to ASD in the family especially complex.

Numerous research efforts have examined family stress and adaptation in autism in comparison to families of children with other developmental disabilities and to families of typically developing children (e.g. Bouma and Schweitzer 1998; Dabrowska and Pisula 2010; Dunn et al. 2001; Eisenhower et al. 2005; Fisman et al. 1989; Perry et al. 2004; Rivers and Stoneman 2003; Rodrigue et al. 1990; Sanders and Morgan 1997). The literature has had a focus on parental depression, marital stress, the quality of the sibling relationship, and similarities and differences in siblings’ experiences and view of their sibling with the disability. There is much inconsistency in the literature, with some studies reporting negative outcomes for families of individuals with autism (e.g. Kaminsky and Dewey 2001; Knott et al. 1995), others reporting no difference in psychopathology and stress levels for families of children with ASD in comparison to those of children with other disabilities (e.g. Hastings 2007; O’Kelley 2007), and still others finding that families of children with ASDs have some positive outcomes (e.g. Kaminsky and Dewey 2001).

Much of the research that has focused on parent adaptation suggests that parents of children with ASD experience significantly more stress than parents of children without disabilities and parents of children with other disabilities (e.g. Bouma and Schweitzer 1990; Dabrowska and Pisula 2010; Dunn et al. 2001; Eisenhower et al. 2005; Fisman et al. 1989; Perry et al. 2004; Rivers and Stoneman 2003; Rodrigue et al. 1990; Sanders and Morgan 1997). Mothers have also reported less perceived parenting competence, less marital satisfaction, and higher levels of depression than mothers of children with typical development or Down syndrome (Fisman et al. 1989;Rivers and Stoneman 2003 Rodrigue et al. 1990). Less work has been done with fathers, although Fisman et al. (1989) also found that fathers of children with ASD experienced more stress and reported less marital intimacy than fathers of children with Down syndrome or typical development. Rivers and Stoneman (2003) found that marital stress was an important predictor of the quality of not only the marital relationship, but also the sibling relationship, such that when marital stress was greater, siblings reported less satisfaction with the sibling relationship, as well as more negative and fewer positive behaviours directed towards their sibling with autism . This research indicates that family systems and the complex interplay of relationships and interactions between family members impact the adjustment and adaptation process. Despite the challenges presented to families raising a child with ASD, some literature suggests that having a child in the family with a disability can present opportunities for growth, challenge, and satisfaction and can promote a sense of self-efficacy to enhance family functioning over time (Blacher et al. 2007; Frain et al. 2007). Furthermore, some parents report that their marriage has been strengthened by the addition of a child with special needs (Blair 1996). This lends support to the models of adaptation that stress the importance of cognitive appraisal in the adjustment and adaptation to having a child on the autism spectrum.

Kaminsky and Dewey (2001) found that relationships between children with ASD and their typically developing siblings were marked by less intimacy, prosocial behaviour, and nurturance than sibling relationships that include a child with Down syndrome or typically developing sibling pairs. In comparison to siblings of children with Down syndrome or typically developing siblings, sibling pairs including a child with ASD reportedly spent less time together, and their initiations (both prosocial and antagonistic) were lower in frequency and variety (Knott et al. 1995) .

Other research, however, has shown that behavioural adjustment of the typically developing sibling is not affected by the diagnostic category of their sibling’s developmental disability. In a longitudinal study by Hastings (2007) comparing the behavioural adjustment of siblings of children with autism, Down syndrome and mixed aetiology mental retardation, no group differences were found in behavioural adjustment of siblings across the diagnostic categories. Further, no evidence was found to support a bidirectional temporal relationship, suggesting that children with developmental disabilities did not appear to be affected by the behavioural adjustment of their typical sibling. Other studies have also failed to uncover differences in adjustment between siblings of children with autism compared to siblings of children with Down syndrome (e.g. O’Kelley 2007).

In an attempt to understand the impact of having a brother or sister with a disability, McHale et al. (1986) interviewed siblings of children with autism, siblings of children with Down syndrome and siblings of typically developing children about their relationship with their sibling, and also interviewed mothers about the sibling relationship. Both siblings of children with ASD and siblings of children with Down syndrome reported a greater admiration of their special needs sibling, and less quarrelling and competition than typical sibling pairs. Based on sibling reports, McHale et al. (1986) found no group differences in the quality of the sibling relationship, however, mothers of children with ASD and those with children with Down syndrome rated their children’s sibling relationships more positively than did mothers of typically developing children. Roeyers and Mycke (1995) interviewed children with a sibling with ASD, Down syndrome or typical development about their sibling relationship, and found that there was a trend for children with a brother or sister with a disability to rate their relationship with the sibling more positively .

Interestingly, positive adjustment outcomes in siblings have been found to be strongly associated with the typically developing sibling’s coping strategies, not the severity of the child’s disability (Macks and Reeve 2007). In their study of adjustment in siblings of children with autism, Macks and Reeve (2007) concluded that adaptive versus maladaptive adjustment was directly related to the presence or absence of demographic risk factors. They found that having a sibling with an ASD appeared to enhance the psychosocial and emotional development of the typically developing sibling when demographic risk factors were limited; however, having a sibling with an ASD had an increasingly unfavourable impact on the sibling relationship as demographic risk factors increased (Macks and Reeve 2007). Interestingly, McHale et al. (1986) found that positive relationships between children with developmental disabilities and their typically developing sibling were reported when the typically developing sibling (a) accepted the child’s role as a member of the family; (b) perceived minimal parental favouritism; (c) had no worry about the future of their sibling; (d) had well-developed coping abilities; (e) understood the sibling’s disability and (f) perceived positive responses from parents and peers towards their sibling. This suggests that siblings’ understanding and appraisal of the situation and their coping abilities, seemingly in addition to reduced demographic risk factors, influence their overall positive adaptation .

The majority of ASD diagnoses are made in the early years of childhood. Parents play a key role in initiating the adaptation process following a diagnosis of autism in the family . It is well documented that stress and burden for parents is elevated in the period surrounding initial diagnosis (Bristol 1987; Howlin and Asgharian 1999), perhaps sensitising parents to mobilise existing coping resources. Many studies examining parental stress and burden in the early stages of diagnosis have been retrospective and have relied on recall of parents regarding their stress levels at the time (Stuart and McGrew 2009). These recall periods have ranged from 1 to 10 years, which influences the reliability of the findings given the impact of recall bias and the fact that families, through the adaptation process across time, will have altered their appraisal about the initial and ongoing impact of the stressor in their lives. Given the crucial role that parents play in the adjustment and adaptation process, it is necessary to understand the factors that impact families following a diagnosis of ASD.

In an attempt to clarify these stressors on families, Stuart and McGrew (2009) studied the application of the Double ABCX model of family adaptation to caregiver burden in ASD in a concurrent research design. Seventy-eight primary caregivers of children diagnosed with ASD within the previous 6 months participated in the study. The variables studied through the Double ABCX model included: severity of the family member’s diagnosis (A), pile-up demands and additional life stressors (Aa); the family’s internal resources (e.g. internal locus of control) (B); the family’s external resources such as social support and finances (bB); the family’s appraisal of the situation as either positive or negative (C); and the coping strategies used (cC) as predictors of the outcome in terms of caregiver (individual, marital and family) burden (X). The Double ABCX model accounted for 81 % of the variance in individual burden and 77 % of the variance in family burden. Caregiver burden (X) was found to be consistently and strongly predicted by autism symptom severity (A), additional pile-up demands (aA), social support (bB), negative appraisal of caring for a child with ASD (C); negative appraisal of the diagnostic experience (C) and the use of passive avoidant coping strategies (cC; Stuart and McGrew 2009) .

Much of the cross-sectional research literature employing group designs indicates that parents of children with mental retardation, ASD and other developmental disorders report greater levels of stress and more mental health problems than parents of typically developing children (Hastings 2007; Quintero and McIntyre 2010). Indeed, mothers of children with ASD report more daily hassles, life stress and depression to mothers without a child with ASD (Quintero and McIntyre 2010). The research literature on parental depression and stress has consistently demonstrated negative outcomes for parents of children with ASD (Quintero and McIntyre 2010) .

Hastings et al. (2005) noted that much of the previous research into family adaptation has viewed the child’s autism as being the stressor and the family members’ wellbeing as being the outcome. However, they proposed a more systemic conceptualisation whereby all family members interact and impact on each other. They evaluated 48 mothers and 41 fathers of pre-school age children with autism to explicitly examine relationships between child, partner and parent variables. They found that mothers reported more depression. However, they also reported more positive perceptions of the child with ASD and their impact on the parent and the wider family compared to fathers. Regression analyses revealed that maternal stress was predicted by their child’s behaviour problems (not adaptive behaviour or autism symptoms) and by their partner’s depression. Paternal stress and positive perceptions were predicted by maternal depression (Hastings et al. 2005). This adds weight to the notion that family interactions are bidirectional and that a systemic approach to researching outcomes is essential to understanding the adaptation process .

Longitudinal research designs have been an important recent addition to the research on the impact of child behaviour problems on parental wellbeing in the general parenting literature. The results of these studies demonstrate a bidirectional relationship between childhood behaviour problems and parental wellbeing (Hastings 2003b). Lecavalier et al. (2006) have demonstrated that, like families of typically developing children, this temporal relationship exists for families with children with ASD as well.

More recent attention has focussed on the trajectories of emotional wellbeing for mothers of adolescents and adults with ASD. In their ongoing longitudinal study of emotional wellbeing of mothers, Barker et al. (2011) found that maternal depression remained relatively stable across the 10-year period of examination with older mothers reporting fewer depressive symptoms at the beginning of the study compared to younger mothers; whereas anxiety declined across the 10-year period with older mothers reporting less anxiety at the start. Barker et al. (2011) argue that this is evidence of resilience, that is, positive adjustment in the face of exceptional stress .

Importantly, in terms of considering early intervention and family support needs, maternal stress and child behaviour problems seem to persist across time. A 2-year longitudinal study conducted by Peters-Scheffer et al. (2012) of 104 mothers of children (aged 2–9 years) with ASD and mental retardation found that maternal stress as measured on the Parenting Stress Index (PSI; Abidin 1995) remained stable across time. Emotionally reactive behaviour, withdrawn behaviour and attention problems of the child significantly predicted maternal stress and these behavioural problems also remained stable across time. This is consistent with previous research that has found that behavioural problems significantly contribute to parental stress and this transaction is bidirectional (Lecavalier et al. 2006) .

Exclusive focus on family functioning as an outcome fails to recognise the transactional interplay of child and family factors over time (Sameroff 2009). Although some authors argue that the neurodevelopmental deficits in autism limit the extent to which family factors may be able to modify the behavioural phenotype (see Baker 2010 for a discussion of biological constraint theories), there is growing evidence that parenting can influence autism-related behaviour even if this behaviour is largely neurobiological in etiology (Baker et al. 2011). A family’s ability to adapt, that is, to remain flexible, to reorganize around new challenges and to develop collaborative and cooperative problem solving is likely to enable individual family members to adapt to the many challenges of family life (Baker et al. 2011), including the unique challenges facing families with a child with ASD. Family level adaptability has been found to predict changes in severity of maternal depression and child behaviour problems 3 years later in families with a child with ASD aged between 10 and 22 years (Baker et al. 2011). However, it may be that the developmental life stages of both the child and the family may account for some of these changes across time .

Greater attention has been paid to the impact of an ASD diagnosis on mothers than fathers possibly because of the ease of access researchers have to mothers. This is a major oversight in the literature and severely disrupts our efforts to predict service and intervention needs of all family members, especially fathers. Indeed it is proposed that fathers require the same information regarding their child’s disability, the same access to resources, programmes, services and treatment as do mothers (Seligman and Darling 2007), however, they may be inadvertently disregarded by service paradigms aimed at mothers .