diff --git a/object/convert.go b/object/convert.go
index 5b4acda..99047dc 100644
--- a/object/convert.go
+++ b/object/convert.go
@@ -270,7 +270,7 @@ func (h *ECHeader) ToGRPCMessage() grpc.Message {
 
 		m.Parent = h.Parent.ToGRPCMessage().(*refsGRPC.ObjectID)
 		m.ParentSplitId = h.ParentSplitID
-		m.ParentSplitIndex = h.ParentSplitIndex
+		m.ParentSplitParentId = h.ParentSplitParentID.ToGRPCMessage().(*refsGRPC.ObjectID)
 		m.Index = h.Index
 		m.Total = h.Total
 		m.Header = h.Header
@@ -303,7 +303,21 @@ func (h *ECHeader) FromGRPCMessage(m grpc.Message) error {
 	}
 
 	h.ParentSplitID = v.GetParentSplitId()
-	h.ParentSplitIndex = v.GetParentSplitIndex()
+
+	parSplitParentID := v.GetParentSplitParentId()
+	if parSplitParentID == nil {
+		h.ParentSplitParentID = nil
+	} else {
+		if h.ParentSplitParentID == nil {
+			h.ParentSplitParentID = new(refs.ObjectID)
+		}
+
+		err = h.ParentSplitParentID.FromGRPCMessage(parSplitParentID)
+		if err != nil {
+			return err
+		}
+	}
+
 	h.Index = v.GetIndex()
 	h.Total = v.GetTotal()
 	h.Header = v.GetHeader()
diff --git a/object/grpc/types.pb.go b/object/grpc/types.pb.go
index 254e76d..3cb44a3 100644
Binary files a/object/grpc/types.pb.go and b/object/grpc/types.pb.go differ
diff --git a/object/marshal.go b/object/marshal.go
index fa2de95..bf8fcb9 100644
--- a/object/marshal.go
+++ b/object/marshal.go
@@ -26,13 +26,13 @@ const (
 	splitHdrChildrenField        = 5
 	splitHdrSplitIDField         = 6
 
-	ecHdrParentField       = 1
-	ecHdrIndexField        = 2
-	ecHdrTotalField        = 3
-	ecHdrHeaderLengthField = 4
-	ecHdrHeaderField       = 5
-	ecHdrParentSplitID     = 6
-	ecHdrParentSplitIndex  = 7
+	ecHdrParentField         = 1
+	ecHdrIndexField          = 2
+	ecHdrTotalField          = 3
+	ecHdrHeaderLengthField   = 4
+	ecHdrHeaderField         = 5
+	ecHdrParentSplitID       = 6
+	ecHdrParentSplitParentID = 7
 
 	hdrVersionField         = 1
 	hdrContainerIDField     = 2
@@ -264,7 +264,7 @@ func (h *ECHeader) StableMarshal(buf []byte) []byte {
 	offset += proto.UInt32Marshal(ecHdrHeaderLengthField, buf[offset:], h.HeaderLength)
 	offset += proto.BytesMarshal(ecHdrHeaderField, buf[offset:], h.Header)
 	offset += proto.BytesMarshal(ecHdrParentSplitID, buf[offset:], h.ParentSplitID)
-	proto.UInt32Marshal(ecHdrParentSplitIndex, buf[offset:], h.ParentSplitIndex)
+	proto.NestedStructureMarshal(ecHdrParentSplitParentID, buf[offset:], h.ParentSplitParentID)
 	return buf
 }
 
@@ -279,7 +279,7 @@ func (h *ECHeader) StableSize() (size int) {
 	size += proto.UInt32Size(ecHdrHeaderLengthField, h.HeaderLength)
 	size += proto.BytesSize(ecHdrHeaderField, h.Header)
 	size += proto.BytesSize(ecHdrParentSplitID, h.ParentSplitID)
-	size += proto.UInt32Size(ecHdrParentSplitIndex, h.ParentSplitIndex)
+	size += proto.NestedStructureSize(ecHdrParentSplitParentID, h.ParentSplitParentID)
 
 	return size
 }
diff --git a/object/test/generate.go b/object/test/generate.go
index bb774cc..95c76e5 100644
--- a/object/test/generate.go
+++ b/object/test/generate.go
@@ -92,7 +92,7 @@ func GenerateECHeader(empty bool) *object.ECHeader {
 	if !empty {
 		ech.Parent = refstest.GenerateObjectID(empty)
 		ech.ParentSplitID = []byte{1, 2, 3}
-		ech.ParentSplitIndex = 1
+		ech.ParentSplitParentID = refstest.GenerateObjectID(empty)
 		ech.Index = 0
 		ech.Total = 2
 		ech.Header = []byte("chunk of ec-encoded parent header")
diff --git a/object/types.go b/object/types.go
index c9a0519..7916b1e 100644
--- a/object/types.go
+++ b/object/types.go
@@ -40,13 +40,13 @@ type SplitHeader struct {
 }
 
 type ECHeader struct {
-	Parent           *refs.ObjectID
-	ParentSplitID    []byte
-	ParentSplitIndex uint32
-	Index            uint32
-	Total            uint32
-	Header           []byte
-	HeaderLength     uint32
+	Parent              *refs.ObjectID
+	ParentSplitID       []byte
+	ParentSplitParentID *refs.ObjectID
+	Index               uint32
+	Total               uint32
+	Header              []byte
+	HeaderLength        uint32
 }
 
 type Header struct {