diff --git a/app/models/group.rb b/app/models/group.rb
index 85a6776a..b8ff9010 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -4,6 +4,15 @@ belongs_to :user
 
 has_many :groupgroup_c, :foreign_key => 'parent_group_id', :class_name => 'Groupgroup'
 has_many :groupgroup_p, :foreign_key => 'group_id', :class_name => 'Groupgroup'
+
+has_many :synapses1, :class_name => 'Synapse', :foreign_key => 'node1_id', :conditions => {:category => 'Group'}
+has_many :synapses2, :class_name => 'Synapse', :foreign_key => 'node2_id', :conditions => {:category => 'Group'}
+has_many :groups1, :through => :synapses2, :source => :group1
+has_many :groups2, :through => :synapses1, :source => :group2
+  
+  def siblings
+     groups1 + groups2
+  end 
   
 has_many :grouppeople
 has_many :groupitems
diff --git a/app/models/item.rb b/app/models/item.rb
index 16d4a46f..52367a26 100644
--- a/app/models/item.rb
+++ b/app/models/item.rb
@@ -11,6 +11,15 @@ has_many :personitems
 has_many :groups, :through => :groupitems
 has_many :people, :through => :personitems
 
+has_many :synapses1, :class_name => 'Synapse', :foreign_key => 'node1_id', :conditions => {:category => 'Item'}
+has_many :synapses2, :class_name => 'Synapse', :foreign_key => 'node2_id', :conditions => {:category => 'Item'}
+has_many :items1, :through => :synapses2, :source => :item1
+has_many :items2, :through => :synapses1, :source => :item2
+  
+  def siblings
+     items1 + items2
+  end 
+
 belongs_to :item_category
 
 has_many :child_items, :through => :itemitem_c, :source => :item
diff --git a/app/models/person.rb b/app/models/person.rb
index 56335233..66deb73d 100644
--- a/app/models/person.rb
+++ b/app/models/person.rb
@@ -6,6 +6,16 @@ has_many :grouppeople
 has_many :personitems
 
 has_many :groups, :through => :grouppeople
+
+has_many :synapses1, :class_name => 'Synapse', :foreign_key => 'node1_id', :conditions => {:category => 'Person'}
+has_many :synapses2, :class_name => 'Synapse', :foreign_key => 'node2_id', :conditions => {:category => 'Person'}
+has_many :people1, :through => :synapses2, :source => :person1
+has_many :people2, :through => :synapses1, :source => :person2
+  
+  def siblings
+     people1 + people2
+  end 
+  
 has_many :items, :through => :personitems
 
 end
diff --git a/app/models/synapse.rb b/app/models/synapse.rb
new file mode 100644
index 00000000..6e5d5e8f
--- /dev/null
+++ b/app/models/synapse.rb
@@ -0,0 +1,14 @@
+class Synapse < ActiveRecord::Base
+
+belongs_to :user
+
+belongs_to :item1, :class_name => "Item", :foreign_key => "node1_id"
+belongs_to :item2, :class_name => "Item", :foreign_key => "node2_id"
+
+belongs_to :person1, :class_name => "Person", :foreign_key => "node1_id"
+belongs_to :person2, :class_name => "Person", :foreign_key => "node2_id"
+
+belongs_to :group1, :class_name => "Group", :foreign_key => "node1_id"
+belongs_to :group2, :class_name => "Group", :foreign_key => "node2_id"
+
+end
diff --git a/config/database.yml b/config/database.yml
index dd462777..eab21bab 100644
--- a/config/database.yml
+++ b/config/database.yml
@@ -12,13 +12,13 @@ development:
 test:
   min_messages: WARNING
   adapter: postgresql
-  host: ec2-54-243-217-241.compute-1.amazonaws.com
+  host: 127.0.0.1
   port: 5432
   encoding: unicode
-  database: dbct9hosrirq2h
+  database: metamap_test
   pool: 5
-  username: tkbwavghytilon
-  password: "To6z-64f1Lr3LqpWrcLBPG2Xdv"
+  username: postgres
+  password: "3112"
 
 production:
   min_messages: WARNING
diff --git a/db/migrate/20121005160234_create_synapses.rb b/db/migrate/20121005160234_create_synapses.rb
new file mode 100644
index 00000000..28c6f599
--- /dev/null
+++ b/db/migrate/20121005160234_create_synapses.rb
@@ -0,0 +1,13 @@
+class CreateSynapses < ActiveRecord::Migration
+  def change
+    create_table :synapses do |t|
+      t.text :desc
+	  t.text :category
+	  t.integer :node1_id
+	  t.integer :node2_id
+	  t.integer :user_id
+
+      t.timestamps
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index c59b9706..547a6dfd 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20120922164150) do
+ActiveRecord::Schema.define(:version => 20121005160234) do
 
   create_table "groupgroups", :force => true do |t|
     t.integer  "group_id"
@@ -91,6 +91,16 @@ ActiveRecord::Schema.define(:version => 20120922164150) do
     t.datetime "updated_at", :null => false
   end
 
+  create_table "synapses", :force => true do |t|
+    t.text     "desc"
+    t.text     "category"
+    t.integer  "node1_id"
+    t.integer  "node2_id"
+    t.integer  "user_id"
+    t.datetime "created_at", :null => false
+    t.datetime "updated_at", :null => false
+  end
+
   create_table "users", :force => true do |t|
     t.string   "name"
     t.string   "email"
diff --git a/test/unit/synapse_test.rb b/test/unit/synapse_test.rb
new file mode 100644
index 00000000..50a6fe66
--- /dev/null
+++ b/test/unit/synapse_test.rb
@@ -0,0 +1,7 @@
+require 'test_helper'
+
+class SynapseTest < ActiveSupport::TestCase
+  # test "the truth" do
+  #   assert true
+  # end
+end