diff --git a/src/App/DocumentObserver.cpp b/src/App/DocumentObserver.cpp
index e6650d5060..789386ba8e 100644
--- a/src/App/DocumentObserver.cpp
+++ b/src/App/DocumentObserver.cpp
@@ -275,7 +275,13 @@ SubObjectT::SubObjectT(SubObjectT &&other)
 
 SubObjectT::SubObjectT(const DocumentObject *obj, const char *s)
     :DocumentObjectT(obj),subname(s?s:"")
-{}
+{
+}
+
+SubObjectT::SubObjectT(const DocumentObjectT& obj, const char *s)
+    :DocumentObjectT(obj),subname(s?s:"")
+{
+}
 
 SubObjectT::SubObjectT(const char *docName, const char *objName, const char *s)
     :DocumentObjectT(docName,objName), subname(s?s:"")
diff --git a/src/App/DocumentObserver.h b/src/App/DocumentObserver.h
index eae3295755..53dea56df7 100644
--- a/src/App/DocumentObserver.h
+++ b/src/App/DocumentObserver.h
@@ -157,6 +157,9 @@ public:
     /*! Constructor */
     SubObjectT(SubObjectT &&);
 
+    /*! Constructor */
+    SubObjectT(const DocumentObjectT & obj, const char *subname);
+
     /*! Constructor */
     SubObjectT(const DocumentObject*, const char *subname);