halfsisters

Half-sisters are female siblings who share one biological parent but not both. They are a subset of siblings and are distinguished from full sisters, who share both parents, and from step-sisters, who are related by marriage rather than by blood. The term half-sister is used in many English-speaking countries, with half-sister and sometimes half-sibling as variants.

Origin and genetic relation: A half-sister arises when two individuals have one parent in common, either the mother or the father. They can be maternal half-sisters (sharing a mother) or paternal half-sisters (sharing a father). In terms of DNA, half-siblings share about 25% of their autosomal DNA on average, though the exact amount can vary due to recombination and other genetic factors.

Social and family dynamics: The nature of the relationship can vary widely. Some half-sisters grow up together and form close bonds; others meet later in life or have limited contact. The presence or absence of shared upbringing, parental custody arrangements, and family history can influence their relationship.

Legal and practical considerations: In many jurisdictions, half-siblings have similar rights to inheritance and parental rights as full siblings, though laws differ. Paternity or maternity determinations may affect legal status in some cases. Adoption, remarriage, and stepfamily dynamics can also intersect with half-sibling relationships.

In genealogy and DNA research, identifying half-siblings can be important for reconstructing family trees. DNA testing can reveal a shared parentage, but precise relationships may require additional documentation or testing of the presumed shared parent.