--- a/accessible/src/base/nsAccessible.cpp
+++ b/accessible/src/base/nsAccessible.cpp
@@ -2824,47 +2824,16 @@ nsAccessible::RemoveChild(nsAccessible* 
   aChild->UnbindFromParent();
   mChildren.RemoveElementAt(index);
   mEmbeddedObjCollector = nsnull;
 
   return PR_TRUE;
 }
 
 nsAccessible*
-nsAccessible::GetParent()
-{
-  if (mParent)
-    return mParent;
-
-  if (IsDefunct())
-    return nsnull;
-
-  // XXX: mParent can be null randomly because supposedly we get layout
-  // notification and invalidate parent-child relations, this accessible stays
-  // unattached. This should gone after bug 572951.
-  NS_WARNING("Bad accessible tree!");
-
-#ifdef DEBUG
-  nsDocAccessible *docAccessible = GetDocAccessible();
-  NS_ASSERTION(docAccessible, "No document accessible for valid accessible!");
-#endif
-
-  nsAccessible* parent = GetAccService()->GetContainerAccessible(mContent,
-                                                                 mWeakShell);
-  NS_ASSERTION(parent, "No accessible parent for valid accessible!");
-  if (!parent)
-    return nsnull;
-
-  // Repair parent-child relations.
-  parent->EnsureChildren();
-  NS_ASSERTION(parent == mParent, "Wrong children repair!");
-  return parent;
-}
-
-nsAccessible*
 nsAccessible::GetChildAt(PRUint32 aIndex)
 {
   if (EnsureChildren())
     return nsnull;
 
   nsAccessible *child = mChildren.SafeElementAt(aIndex, nsnull);
   if (!child)
     return nsnull;

--- a/accessible/src/base/nsAccessible.h
+++ b/accessible/src/base/nsAccessible.h
@@ -256,17 +256,17 @@ public:
   virtual PRBool RemoveChild(nsAccessible* aChild);
 
   //////////////////////////////////////////////////////////////////////////////
   // Accessible tree traverse methods
 
   /**
    * Return parent accessible.
    */
-  virtual nsAccessible* GetParent();
+  nsAccessible* GetParent() const { return mParent; }
 
   /**
    * Return child accessible at the given index.
    */
   virtual nsAccessible* GetChildAt(PRUint32 aIndex);
 
   /**
    * Return child accessible count.

--- a/accessible/src/base/nsApplicationAccessible.cpp
+++ b/accessible/src/base/nsApplicationAccessible.cpp
@@ -405,22 +405,16 @@ nsApplicationAccessible::GetStateInterna
 
 void
 nsApplicationAccessible::InvalidateChildren()
 {
   // Do nothing because application children are kept updated by AppendChild()
   // and RemoveChild() method calls.
 }
 
-nsAccessible*
-nsApplicationAccessible::GetParent()
-{
-  return nsnull;
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // nsAccessible protected methods
 
 void
 nsApplicationAccessible::CacheChildren()
 {
   // CacheChildren is called only once for application accessible when its
   // children are requested because empty InvalidateChldren() prevents its

--- a/accessible/src/base/nsApplicationAccessible.h
+++ b/accessible/src/base/nsApplicationAccessible.h
@@ -126,18 +126,16 @@ public:
 
   // nsAccessible
   virtual nsresult GetARIAState(PRUint32 *aState, PRUint32 *aExtraState);
   virtual PRUint32 NativeRole();
   virtual nsresult GetStateInternal(PRUint32 *aState, PRUint32 *aExtraState);
 
   virtual void InvalidateChildren();
 
-  virtual nsAccessible* GetParent();
-
 protected:
 
   // nsAccessible
   virtual void CacheChildren();
   virtual nsAccessible* GetSiblingAtOffset(PRInt32 aOffset,
                                            nsresult *aError = nsnull);
 
 private:

--- a/accessible/tests/mochitest/events/test_docload.html
+++ b/accessible/tests/mochitest/events/test_docload.html
@@ -122,21 +122,16 @@
     {
       // Get application root accessible.
       var docAcc = getAccessible(document);
       while (docAcc) {
         this.mRootAcc = docAcc;
         try {
           docAcc = docAcc.parent;
         } catch (e) {
-          // XXX: it may randomaly fail on propertypage accessible of browser's
-          // tabbbrowser if nsIAccessible::parent returns cached parent only.
-          // This should gone after bug 572951.
-          // Error: failed | Can't get parent for [ 'panel1277435313424' ,
-          // role: propertypage]
           ok(false, "Can't get parent for " + prettyName(docAcc));
           throw e;
         }
       }
 
       this.eventSeq = [
         new invokerChecker(EVENT_REORDER, this.mRootAcc)
       ];