diff --git a/go.mod b/go.mod
index 01f6c9c..690ceee 100644
--- a/go.mod
+++ b/go.mod
@@ -4,7 +4,7 @@ go 1.24
 
 require (
 	github.com/RoaringBitmap/roaring/v2 v2.4.5
-	github.com/blevesearch/bleve_index_api v1.2.12-0.20260109154621-f19a6d6af728
+	github.com/blevesearch/bleve_index_api v1.2.12-0.20260109165046-049020a048f7
 )
 
 require (
diff --git a/go.sum b/go.sum
index 48edeeb..b1c25ee 100644
--- a/go.sum
+++ b/go.sum
@@ -2,8 +2,8 @@ github.com/RoaringBitmap/roaring/v2 v2.4.5 h1:uGrrMreGjvAtTBobc0g5IrW1D5ldxDQYe2
 github.com/RoaringBitmap/roaring/v2 v2.4.5/go.mod h1:FiJcsfkGje/nZBZgCu0ZxCPOKD/hVXDS2dXi7/eUFE0=
 github.com/bits-and-blooms/bitset v1.12.0 h1:U/q1fAF7xXRhFCrhROzIfffYnu+dlS38vCZtmFVPHmA=
 github.com/bits-and-blooms/bitset v1.12.0/go.mod h1:7hO7Gc7Pp1vODcmWvKMRA9BNmbv6a/7QIWpPxHddWR8=
-github.com/blevesearch/bleve_index_api v1.2.12-0.20260109154621-f19a6d6af728 h1:qFnvr+SqVOCbhMl5sVynhuwVkv1yrc7Vhrn8lVdw1nU=
-github.com/blevesearch/bleve_index_api v1.2.12-0.20260109154621-f19a6d6af728/go.mod h1:xvd48t5XMeeioWQ5/jZvgLrV98flT2rdvEJ3l/ki4Ko=
+github.com/blevesearch/bleve_index_api v1.2.12-0.20260109165046-049020a048f7 h1:4sr3ewS5WzEDz9bwjQ4vrq/nIhBD1FXcCkvecd8OKfE=
+github.com/blevesearch/bleve_index_api v1.2.12-0.20260109165046-049020a048f7/go.mod h1:xvd48t5XMeeioWQ5/jZvgLrV98flT2rdvEJ3l/ki4Ko=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
diff --git a/segment.go b/segment.go
index 122a28d..4e2dbad 100644
--- a/segment.go
+++ b/segment.go
@@ -243,3 +243,24 @@ type Synonym interface {
 
 	Size() int
 }
+
+// NestedSegment is an optional interface that a Segment may implement
+// to provide access to nested document relationships within that segment.
+type NestedSegment interface {
+	Segment
+	// Ancestors returns a slice of ancestor IDs for the given document ID.
+	// If the document has no ancestors or if the segment does not support nested documents,
+	// a slice containing only the document ID itself is returned.
+	Ancestors(docID uint64, prealloc []index.AncestorID) []index.AncestorID
+
+	// CountRoot returns the number of root documents in the segment, excluding any documents
+	// that are marked as deleted in the provided bitmap. If the segment does not support nested
+	// documents, it returns the total document count minus the count of deleted documents.
+	// A root document is defined as a document that is not a child of any other document.
+	CountRoot(deleted *roaring.Bitmap) uint64
+
+	// AddNestedDocuments updates the provided bitmap to include all nested documents
+	// associated with documents marked as deleted in the bitmap. This ensures that when
+	// a parent document is deleted, all its nested child documents are also considered deleted.
+	AddNestedDocuments(deleted *roaring.Bitmap) *roaring.Bitmap
+}