SELECT DISTINCT Child.successionID
INTO :successionID
FROM EvidenceDescriptor Child
INNER JOIN EvidenceRelationship ON Child.evidenceType = EvidenceRelationship.childType
AND Child.relatedID = EvidenceRelationship.childID
INNER JOIN EvidenceDescriptor Parent ON Parent.evidenceType = EvidenceRelationship.parentType
AND Parent.relatedID = EvidenceRelationship.parentID
WHERE Parent.successionID = :relatedSuccessionID