As Rebecca Hegar (in press) points out, “surprising controversies arise over the meaning of the word, ‘siblings’.”  Tracing historical roots, “siblings” most literally means “little kinfolk” (Hegar, in press).  In contemporary society, the meaning of “sibling” needs to be considered from two perspectives: the child’s or youth’s view of who is his/her sibling and the state’s legal definition of sibling.

The identification of a “sibling” can be challenging, particularly when children have lived in more than one family.  Children’s and youth’s definitions of their siblings often differ from that of the child welfare system or legislative definitions of siblings.   Children and youth involved with the child welfare system may have ties with many different types of other children/youth whom they may regard as their “siblings”:

• Full or half biological brothers and sisters, including children who were placed for adoption at birth or removed from the home for other reasons
• Step-brothers and step-sisters
• Other children of the child’s adoptive parent(s)
• Other children living in the home of the parents or relatives with whom the child resides who may or may be biologically related to the child 
• Children of the partner or former partner of the child’s parent
• Children of the child’s godparents
• Other children in foster care living with the child in the same foster family
• Other youth in group home settings where the youth has developed close, enduring relationships

Children and youth may see any or all of these other children and youth as important supports for them.  In other instances, a child may not identify a biological brother or sister as a “sibling” for a variety of reasons but may strongly relate to a non-biological relationship as a sibling relationship.  For those reasons, the child may be the best source of information regarding whom he/she considers a “sibling”.

The Fostering Connections Act does not define “sibling” and the Children’s Bureau has not issued regulation or policy that defines “siblings” or “sibling groups”.  A title IV-E agency has the flexibility to define these terms for the purpose of the Fostering Connections sibling placement provision.  States vary in their definition of sibling relationships.   Legal definitions of siblings have traditionally been confined to children with biological or legal connections, but there has been an increasing recognition that with the current diversity of family structure, a broader definition of “sibling” may be needed.  Familial relationships and clan membership may shape the definition of “sibling” for American Indian/Alaskan Native children.

California  defines “sibling” as “a child related to another person by blood, adoption, or affinity through a common legal or biological parent.”

Colorado defines “sibling” as “a sibling from birth who is descended from one or two mutual parents or a stepbrother or former stepbrother or a stepsister or former stepsister.”

Florida  defines “sibling” as another child who resides with or is cared for by the parent or parents regardless of whether the child is related legally or by consanguinity.

Indianadefines “sibling” as (1) a biological brother or sister; (2) an adoptive brother or sister; (3) a foster brother or sister; or (4) a stepbrother or stepsister.

Oregon defines “sibling” as one of two or more children or wards related: (a) By blood or adoption through a common legal parent; or (b) Through the marriage of the children's or wards' legal or biological parents. 

West Virginia defines “sibling” 49-1-3 as children who have at least one biological parent in common or who have been legally adopted by the same parents or parent.

Children’s Defense Fund.  (2009). The Fostering Connections To Success Act:  Maintaining Sibling Relationships. Retrieved February 20, 2012 from http://www.childrensdefense.org/child-research-data-publications/data/FCSIAA-maintaining-sibling-connections.pdf

Hegar, R. (in press). Sibling issues in child welfare. In G. Hallon and P. Hess (Eds.).  Child Welfare in the 21st Century, Second Edition.  New York: Columbia University Press.