This chapter will explore typical sibling relationships as a basis for understanding the impact of brain injury on the sibling relationship discussed in later chapters. It will first consider aspects of the sibling relationship which make it a unique family relationship. It will then explore sibling relationships across childhood, adolescence and adulthood.
Unique aspects of the sibling relationship
The sibling relationship is unique among family relationships because of its duration, egalitarian nature, high degree of familiarity and emotional complexity. It is the longest family connection people will have, usually from birth to death (Cicirelli, 1995; White & Hughes, 2017). Research in Australia, for example, suggests that among people aged 75 years or older 43 per cent have monthly contact with a sibling (Baxter, 2016). Indeed, siblings may influence each other from before birth, when parents prepare their child for the arrival of a new sibling, and even after death, as the memory of a sibling emotionally impacts a person (Cicirelli, 1995). Being someone's sibling is a role which is not usually chosen. You become a sibling through birth or a legal process such as marriage or adoption. As a result, although siblings may become estranged and their relationship may end, their status as siblings remains unchanged. It is always possible, therefore, for the relationship to be rekindled later in life, something which is less likely among estranged friends.
The sibling relationship is also unique because is it relatively egalitarian, especially when siblings are older (Cicirelli, 1995). Unlike other family relationships, the sibling relationship includes complementary or hierarchical interactions similar to parentāchild exchanges, and reciprocal interactions similar to peer exchanges (Howe et al., 2011). Consider, for example, an interaction between two pre-school siblings where the older sibling teaches the younger sibling a new game. The older sibling's role is similar to the parent teaching the younger child a new skill. Then consider these siblings when they are older, perhaps 10 and 12 years old. They play together, and both contribute to the game, teaching each other skills. Here they relate to each other as equals influencing each other's development. Of course, across the lifespan, siblingsā interactions will not always be equal. Indeed siblings may enjoy different statuses within the relationship due to broader factors such as their cultural background, family size and dynamics, or differing social or economic success as adults (Cicirelli, 1995).
Another unique aspect of the sibling relationship is that siblings usually share a strong sense of familiarity (Cicirelli, 1995; White & Hughes, 2017). Growing up in the same household facilitates the development of shared characteristics and shared histories, creating deep bonds between siblings. As a result, a sense of solidarity based on childhood memories may be formed, and this can be hard to achieve in other relationships (Kramer, 2010). Sibling familiarity, however, is a ādouble-edged swordā because it also provides siblings with the unique knowledge of how to expertly tease and annoy each other (Kramer, 2010).
Furthermore, this familiarity creates the backdrop for the emotionally-charged and uninhibited interactions which are typical of the sibling relationship (Howe et al., 2011; White & Hughes, 2017). Thus, not only do siblings know exactly how to tease or annoy their brothers or sisters, they can also challenge them by displaying anger and frustration without jeopardising the relationship. In other words, they know that no matter how angry they get with their sibling, they will continue to be siblings. By contrast, similar expressions of anger and frustration towards friends could risk the friendship (White & Hughes, 2017).
As a result of the relative permanency of the sibling relationship and the high degree of familiarity between siblings, the sibling relationship can involve emotional extremes. Strong positive and negative feelings characterise the sibling relationship, and siblingsā interactions may quickly switch from harmonious to hostile, often for unclear reasons (Kramer, 2010). Some researchers have suggested considering this emotional ambivalence as an essential part of the relationship (Howe et al., 2011; Kramer, 2010). When talking to people about their sibling relationship within the context of brain injury, this mix of conflict and closeness was often their starting point. Irrespective of whether they had a brain injury or were the sibling of someone with a brain injury, they saw their relationship as naturally involving emotional extremes of love and hate. These emotions were intensely experienced and seen as a very natural aspect of being siblings. Sally, a young adult whose sibling has a brain injury, started by describing their relationship as ākind of a weird mix between very normal sibling behaviour of wanting to rip each other's heads off and the closeness that comes with thatā.
Conflict within the sibling relationship occurs frequently. For example, observational studies have suggested that children may have up to eight sibling interactions per hour that involve conflict (Howe et al., 2011). Siblings, particularly in childhood, spend a considerable amount of time together which means they must share space and property and interact over long periods of time (Howe et al., 2011). Within this context, it is natural for their goals and desires to differ, leading to arguments (Howe et al., 2011). Jon, a young adult with ABI, described such interactions with his sibling:
I feel like [when] we get along it's great, but I think we do get sick of each other very quickly ā¦ So when things are good, theyāre really good, but when things are bad, we canāt stand each other.
As well as experiencing conflict, siblings, from childhood through to adulthood, also act as companions and confidants, and siblingsā intimate knowledge of each other means they can provide lifelong support (Cicirelli, 1991; McHale et al., 2012). The next section explores further this sense of connection and support across the lifespan, including the roles siblings fulfil at different life stages.
Sibling relationships across the lifespan
The sibling relationship is often the longest family relationship a person will experience. Siblings usually play a role in each other's lives across the lifespan, from childhood to older adulthood. Yet, the majority of research examining the sibling relationship has focused on childhood and adolescence. However, some researchers have attempted to redress this. Their work has suggested that siblings fulfil important roles across the lifespan with perhaps some roles being more prominent at particular life stages (Cicirelli, 1995; Goetting, 1986). This section will provide a brief overview of the sibling relationship across childhood, adolescence and adulthood, with a focus on roles siblings fulfil and factors which may influence the relationship.
Early to middle childhood
In childhood and adolescence, siblings often live together and during this time they are likely to spend a considerable amount of time together, especially if they are close in age (Dunn, 1989; Howe et al., 2011). The number of interactions they have during this time means that siblings have a considerable impact on each other's development (McHale et al., 2012). Childhood is also the life stage when siblings form close bonds with each other and develop a sense of familiarity that may characterise their relationship into adulthood (Howe et al., 2011). During childhood, siblings (Youngblade & Dunn, 1995) fulfil roles as companions and teachers, but also combatants (McHale et al., 2012).
From early childhood, siblings act as playmates and companions. In observational studies of pre-school siblings playing together, Dunn (1989) commented that the interactions siblings displayed were surprisingly complex, given their young ages. Thus, pre-school siblings from about two years of age and older planned the rules and scenarios of their pretend play (e.g. āPretend youāre a baby or my mummyā) and the emotions and behaviours they were to act out (e.g. āMe canāt get to sleepā) (Dunn, 1989, p. 111). Such games require children to develop their social understanding, that is an understanding of othersā intentions and feelings and of the rules which govern social interactions (Dunn, 1989). Furthermore, although children may engage in pretend play with parents, research suggests that pre-schoolers engage more in such play with each other than with parents. Siblings are much more likely to enjoy an imaginative game than parents and the shared enjoyment gives this interaction a different quality to parentāchild play (White & Hughes, 2017). In interviewing siblings about their relationship, this role of siblings as playmates and companions was frequently mentioned, as Paul, a child whose sibling has an ABI explained:
I got lots of them [games], so there's always something you can do. ā¦ If youāre the only child, you canāt really play with anyone at home. So it's good fun that. Hang out [with your siblings].
Indeed, even before the birth of younger siblings, the expectation of companionship is there. Alex, a young adult with an ABI, discussed this as he reflected on in his childhood before having siblings:
Being on the farm ā¦ there's no one there to really play with. ā¦ I wanted somebody there to play with, you know? It's what I asked Mum and Dad for Christmas for every year. āI want a brother.ā ā¦ So it was just to have somebody, have somebody else young and around that we could do stuff. ā¦ I just wanted another kid around to do stuff with.
Play with siblings can provide essential opportunities to develop skills. Imaginative play, for example, provides siblings with opportunities to engage in a symbolic representation of the world, and such engagement forms an integral part of a child's development (Kramer, 2010). Siblingsā play also provides opportunities to experience positive interactions, creating the foundations of the sibling bond. Furthermore, play interactions, as well as observations of interactions between older siblings and parents, provide opportunities for younger siblings to develop language and conversation skills (Dunn, 1989). The sibling relationship in early childhood, therefore, provides opportunities for siblings to explore and master their environment through observation, imitation and play (Teti et al., 1989).
During childhood, sibling interactions lead to another important role as teachers and guides, especially for older siblings who may model skills for younger siblings to emulate, as well as actively teaching them new skills. Frederic, an adult with an ABI, reflected on many of these aspects when recollecting his childhood with his older siblings:
We were always really close as kids. ā¦ I learned to walk and talk quickest out of all three of us ...
