http://hl7.org/fhir/StructureDefinition/family-member-history-genetics-sibling|4.0.1

Identifies a sibling of the relative.

Name	Card	Type	Description & Constraints
Extension	0..*		natural brother(s) & natural sister(s) - genetic & other
extension *	1..1	Extension	sibling \| brother \| sister \| etc.
extension	?..0
url	?..?	uri
value[x] *	1..?		SiblingRelationshipType (required)
valueCodeableConcept *	1..?	CodeableConcept	SiblingRelationshipType (required)
extension *	1..1	Extension	Link to sibling relative(s)
extension	?..0
url	?..?	uri
value[x] *	1..?
valueReference *	1..?	Reference
url	?..?
value[x]	0..0