diff --git a/include/xo/stringtable2/DString.hpp b/include/xo/stringtable2/DString.hpp
index cdb362d..75090f2 100644
--- a/include/xo/stringtable2/DString.hpp
+++ b/include/xo/stringtable2/DString.hpp
@@ -7,6 +7,7 @@
 
 #include <xo/alloc2/Allocator.hpp>
 #include <xo/alloc2/Collector.hpp>
+#include <xo/alloc2/GCObjectVisitor.hpp>
 #include <xo/facet/obj.hpp>
 #include <xo/indentlog/print/ppindentinfo.hpp>
 #include <string_view>
@@ -47,6 +48,8 @@ namespace xo {
             using AAllocator = xo::mm::AAllocator;
             /** garbage collector **/
             using ACollector = xo::mm::ACollector;
+            /** object visitor (garbage collector proxy) **/
+            using AGCObjectVisitor = xo::mm::AGCObjectVisitor;
             /** ppindentinfo for APrintable **/
             using ppindentinfo = xo::print::ppindentinfo;
             ///@}
@@ -247,10 +250,10 @@ namespace xo {
             /** clone string, using memory from allocator @p mm **/
             DString * shallow_move(obj<ACollector> gc) noexcept;
 
-            size_type forward_children(obj<ACollector> gc) noexcept;
             /** fixup child pointers (trivial for DString, no children)
              *  note: cref so we can use forward decl
              **/
+            void visit_gco_children(obj<AGCObjectVisitor> gc) noexcept;
 
             ///@}
 
diff --git a/include/xo/stringtable2/DUniqueString.hpp b/include/xo/stringtable2/DUniqueString.hpp
index 71427c4..7e3502b 100644
--- a/include/xo/stringtable2/DUniqueString.hpp
+++ b/include/xo/stringtable2/DUniqueString.hpp
@@ -27,6 +27,7 @@ namespace xo {
         public:
             using AAllocator = xo::mm::AAllocator;
             using ACollector = xo::mm::ACollector;
+            using AGCObjectVisitor = xo::mm::AGCObjectVisitor;
             using size_type = DString::size_type;
             using ppindentinfo = xo::print::ppindentinfo;
 
@@ -92,7 +93,7 @@ namespace xo {
             DUniqueString * shallow_move(obj<ACollector> gc) noexcept;
 
             /** fixup child pointers (trivial for DUniqueString, no gc-owned children **/
-            void forward_children(obj<ACollector> gc) noexcept;
+            void visit_gco_children(obj<AGCObjectVisitor> gc) noexcept;
 
             ///@}
 
diff --git a/include/xo/stringtable2/string/IGCObject_DString.hpp b/include/xo/stringtable2/string/IGCObject_DString.hpp
index 4eaa9dc..6fcbd3b 100644
--- a/include/xo/stringtable2/string/IGCObject_DString.hpp
+++ b/include/xo/stringtable2/string/IGCObject_DString.hpp
@@ -44,6 +44,7 @@ namespace xo {
             using size_type = xo::mm::AGCObject::size_type;
             using AAllocator = xo::mm::AGCObject::AAllocator;
             using ACollector = xo::mm::AGCObject::ACollector;
+            using AGCObjectVisitor = xo::mm::AGCObject::AGCObjectVisitor;
             using Copaque = xo::mm::AGCObject::Copaque;
             using Opaque = xo::mm::AGCObject::Opaque;
             ///@}
@@ -54,8 +55,10 @@ namespace xo {
             // non-const methods
             /** move instance using allocator **/
             static Opaque shallow_move(DString & self, obj<ACollector> gc) noexcept;
-            /** during GC: forward immdiate children **/
-            static void forward_children(DString & self, obj<ACollector> gc) noexcept;
+            /** Invoke fn.visit_child(iface,data) for each child GCObject pointer.
+Context: provides address of data pointer so it can be updated in place
+when @p fn invokes garbage collector reentry point **/
+            static void visit_gco_children(DString & self, obj<AGCObjectVisitor> fn) noexcept;
             ///@}
         };
 
diff --git a/include/xo/stringtable2/uniquestring/IGCObject_DUniqueString.hpp b/include/xo/stringtable2/uniquestring/IGCObject_DUniqueString.hpp
index b6e1d19..a175565 100644
--- a/include/xo/stringtable2/uniquestring/IGCObject_DUniqueString.hpp
+++ b/include/xo/stringtable2/uniquestring/IGCObject_DUniqueString.hpp
@@ -44,6 +44,7 @@ namespace xo {
             using size_type = xo::mm::AGCObject::size_type;
             using AAllocator = xo::mm::AGCObject::AAllocator;
             using ACollector = xo::mm::AGCObject::ACollector;
+            using AGCObjectVisitor = xo::mm::AGCObject::AGCObjectVisitor;
             using Copaque = xo::mm::AGCObject::Copaque;
             using Opaque = xo::mm::AGCObject::Opaque;
             ///@}
@@ -54,8 +55,10 @@ namespace xo {
             // non-const methods
             /** move instance using allocator **/
             static Opaque shallow_move(DUniqueString & self, obj<ACollector> gc) noexcept;
-            /** during GC: forward immdiate children **/
-            static void forward_children(DUniqueString & self, obj<ACollector> gc) noexcept;
+            /** Invoke fn.visit_child(iface,data) for each child GCObject pointer.
+Context: provides address of data pointer so it can be updated in place
+when @p fn invokes garbage collector reentry point **/
+            static void visit_gco_children(DUniqueString & self, obj<AGCObjectVisitor> fn) noexcept;
             ///@}
         };
 
diff --git a/src/stringtable2/DString.cpp b/src/stringtable2/DString.cpp
index c3340f4..7bd16fb 100644
--- a/src/stringtable2/DString.cpp
+++ b/src/stringtable2/DString.cpp
@@ -172,10 +172,10 @@ namespace xo {
             return copy;
         }
 
-        auto
-        DString::forward_children(obj<ACollector>) noexcept -> size_type
+        void
+        DString::visit_gco_children(obj<AGCObjectVisitor>) noexcept
         {
-            return shallow_size();
+            // no-op.  no children!
         }
 
         bool
diff --git a/src/stringtable2/DUniqueString.cpp b/src/stringtable2/DUniqueString.cpp
index 43e7f1c..2660e5d 100644
--- a/src/stringtable2/DUniqueString.cpp
+++ b/src/stringtable2/DUniqueString.cpp
@@ -109,9 +109,9 @@ namespace xo {
         }
 
         void
-        DUniqueString::forward_children(obj<ACollector>) noexcept
+        DUniqueString::visit_gco_children(obj<AGCObjectVisitor>) noexcept
         {
-            // no-op
+            // no-op -- childless!
         }
     } /*namespace scm*/
 } /*namespace xo*/
diff --git a/src/stringtable2/IGCObject_DString.cpp b/src/stringtable2/IGCObject_DString.cpp
index d838e65..f77077b 100644
--- a/src/stringtable2/IGCObject_DString.cpp
+++ b/src/stringtable2/IGCObject_DString.cpp
@@ -21,9 +21,9 @@ namespace xo {
             return self.shallow_move(gc);
         }
         auto
-        IGCObject_DString::forward_children(DString & self, obj<ACollector> gc) noexcept -> void
+        IGCObject_DString::visit_gco_children(DString & self, obj<AGCObjectVisitor> fn) noexcept -> void
         {
-            self.forward_children(gc);
+            self.visit_gco_children(fn);
         }
 
     } /*namespace scm*/
diff --git a/src/stringtable2/IGCObject_DUniqueString.cpp b/src/stringtable2/IGCObject_DUniqueString.cpp
index 60a4d9b..a259148 100644
--- a/src/stringtable2/IGCObject_DUniqueString.cpp
+++ b/src/stringtable2/IGCObject_DUniqueString.cpp
@@ -21,9 +21,9 @@ namespace xo {
             return self.shallow_move(gc);
         }
         auto
-        IGCObject_DUniqueString::forward_children(DUniqueString & self, obj<ACollector> gc) noexcept -> void
+        IGCObject_DUniqueString::visit_gco_children(DUniqueString & self, obj<AGCObjectVisitor> fn) noexcept -> void
         {
-            self.forward_children(gc);
+            self.visit_gco_children(fn);
         }
 
     } /*namespace scm*/