stepsis

Stepsiblings (sometimes abbreviated informally as stepsibs) is the generic term for stepsisters and stepbrothers. Step-siblings are usually regarded as connected only by law and/or social norms, and are not necessarily genetically related – unless they are also half-siblings or another kind of blood relative. Technically, a step-sibling can be related to a stepbrother or stepsister only if they are born before their biological parents are divorced or widowed, and a remarriage occurs, involving one biological parent of each step-sibling.

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