Sibling incest

Siblings play a unique role in one another’s lives that simulates the companionship of parents as well as the power and assistance of friends. Because siblings often grow up in the same household, they have a large amount of exposure to one another, like other members of the immediate family. However, though a sibling relationship can have both hierarchical and reciprocal elements, this relationship tends to be more egalitarian and symmetrical than with family members of other generations. Furthermore, sibling relationships often reflect the overall condition of cohesiveness within a family.

Siblings generally spend more time with each other during childhood than they do with parents or anyone else, and sibling relationships are often the longest-lasting relationship in individuals’ lives.

The content and context of sibling relationships varies between cultures. In industrialized cultures, sibling relationships are typically discretionary in nature. People are encouraged to stay in contact and cooperate with their brothers and sisters, but this is not an obligation. Older siblings in these cultures are sometimes given responsibilities to watch over a younger sibling, but this is only occasional, with parents taking on the primary role of caretaker. In contrast, close sibling relationships in nonindustrialized cultures are often obligatory, with strong cultural norms prompting cooperation and close proximity between siblings. In India, the sibling relationship is so cherished that a festival is held in observance called Rakhi. At this celebration, the sister presents the brother with a woven bracelet to show their lasting bond even when they have raised their own families. These cultures also extend caregiving roles to older siblings, who are constantly expected to watch over younger siblings.

A relationship begins with the introduction of two siblings to one another. Older siblings are often made aware of their soon-to-be younger brother or sister at some point during their mother’s pregnancy, which may help facilitate adjustment for the older child and result in a better immediate relationship with the newborn. Early in development, interactions can contribute to the older sibling’s social aptitude and cognitively stimulate the younger sibling. Older siblings even adapt their speech to accommodate for the low language comprehension of the younger sibling, much like parents do with baby talk.

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Wikipedia