Life course studies of siblings of individuals with developmental disabilities.

The sibling relationship constitutes the longest lasting family tie, beginning with the birth of the younger sibling and ending with the death of one member of the sibling pair. Siblings share a common family heritage, both genetically and experientially, and perhaps for this reason, the sibling relationship is normatively characterized as egalitarian, reciprocal, and mutual. How is the sibling relationship distinct when one member of the sibling pair has a developmental disability? Aspects of the sibling tie might be atypical in this context, in several respects. For example, the duration of the relationship might be shorter, as some individuals with developmental disabilities have a more limited life-span. In addition, there may be less genetic and experiential similarity between members of the sib pair and less egalitarianism and reciprocal exchange due to unequal abilities and patterns of life course outcomes. However, there may also be greater continuity in contact across the life course when the sibling has a developmental disability. Most past researchers of siblings of individuals with developmental disabilities have focused on the sibling pair during childhood (Stoneman, 1998; Stoneman & Berman, 1993). However, individuals with developmental disabilities tend to live well into adulthood and now commonly reach old age. Therefore, there is a need to extend our investigation of the sibling relationship when one has a developmental disability across the life course to better elucidate whether and how this relationship changes when the siblings grow up. Among the general population, the sibling relationship has significant life course variation, as the intense involvement that characterizes sibling interactions during childhood give way to more disengaged relationships during the young adult years, followed by a reintensification of the sibling bond during midlife and older age (Cicirelli, 1982; Goetting, 1986). How these life course patterns are manifested when one sibling has a developmental disability is the focus of this review. Life Course Studies of Siblings of Individuals With Developmental Disabilities