diff --git a/accessible/generic/BaseAccessibles.cpp b/accessible/generic/BaseAccessibles.cpp
index 04c31d39bb5..c2fcf66982f 100644
--- a/accessible/generic/BaseAccessibles.cpp
+++ b/accessible/generic/BaseAccessibles.cpp
@@ -53,6 +53,13 @@ LeafAccessible::RemoveChild(Accessible* aChild)
   return false;
 }
 
+bool
+LeafAccessible::IsAcceptableChild(nsIContent* aEl) const
+{
+  // No children for leaf accessible.
+  return false;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // LeafAccessible: Accessible private
 
diff --git a/accessible/generic/BaseAccessibles.h b/accessible/generic/BaseAccessibles.h
index 71e932949b4..8e8a9298493 100644
--- a/accessible/generic/BaseAccessibles.h
+++ b/accessible/generic/BaseAccessibles.h
@@ -38,6 +38,8 @@ public:
   virtual bool InsertChildAt(uint32_t aIndex, Accessible* aChild) override final;
   virtual bool RemoveChild(Accessible* aChild) override final;
 
+  virtual bool IsAcceptableChild(nsIContent* aEl) const override;
+
 protected:
   virtual ~LeafAccessible() {}