diff --git a/src/ecma119_tree.c b/src/ecma119_tree.c
index 7f1969a..e4d1370 100644
--- a/src/ecma119_tree.c
+++ b/src/ecma119_tree.c
@@ -651,6 +651,9 @@ int reparent(Ecma119Node *child, Ecma119Node *parent)
         return ISO_ERROR;
     }
 
+    /* keep track of the real parent */
+    child->info.dir.real_parent = child->parent;
+    
     /* add the child to its new parent */
     child->parent = parent;
     parent->info.dir.nchildren++;
diff --git a/src/ecma119_tree.h b/src/ecma119_tree.h
index d609414..12a55ba 100644
--- a/src/ecma119_tree.h
+++ b/src/ecma119_tree.h
@@ -29,6 +29,11 @@ struct ecma119_dir_info {
 
     size_t nchildren;
     Ecma119Node **children;
+    
+    /** 
+     * Real parent if the dir has been reallocated. NULL otherwise.
+     */
+    Ecma119Node *real_parent;
 };
 
 /**
@@ -51,6 +56,8 @@ struct ecma119_node
     enum ecma119_node_type type; 
     union {
         IsoFileSrc *file;
+        // TODO this wastes too much memory, as dirs have much more
+        // atts than other kind of files. Replace with a pointer.
         struct ecma119_dir_info dir;
         /** this field points to the relocated directory. */
         Ecma119Node *real_me;