diff --git a/lib/factory_girl/factory.rb b/lib/factory_girl/factory.rb
index 8fda985..14307a8 100644
--- a/lib/factory_girl/factory.rb
+++ b/lib/factory_girl/factory.rb
@@ -45,7 +45,11 @@ module FactoryGirl
 
       new_attributes = []
       parent.attributes.each do |attribute|
-        unless attribute_defined?(attribute.name)
+        if attribute_defined?(attribute.name)
+          @attributes.delete_if do |attrib|
+            new_attributes << attrib.clone if attrib.name == attribute.name
+          end
+        else
           new_attributes << attribute.clone
         end
       end
diff --git a/spec/acceptance/parent_spec.rb b/spec/acceptance/parent_spec.rb
index a803c9a..5706e4f 100644
--- a/spec/acceptance/parent_spec.rb
+++ b/spec/acceptance/parent_spec.rb
@@ -3,12 +3,13 @@ require 'acceptance/acceptance_helper'
 
 describe "an instance generated by a factory that inherits from another factory" do
   before do
-    define_model("User", :name => :string, :admin => :boolean, :email => :string, :upper_email => :string)
+    define_model("User", :name => :string, :admin => :boolean, :email => :string, :upper_email => :string, :login => :string)
 
     FactoryGirl.define do
       factory :user do
         name  "John"
         email { "#{name.downcase}@example.com" }
+        login { email }
 
         factory :admin do
           name "admin"
@@ -43,6 +44,7 @@ describe "an instance generated by a factory that inherits from another factory"
     it          { should_not be_admin }
     its(:name)  { should == "John" }
     its(:email) { should eql "John-guest@example.com" }
+    its(:login) { should == "John-guest@example.com" }
   end
 end