added children to users

front-api/models/child.rb

@@ -0,0 +1,3 @@
+class Child < ActiveRecord::Base
+    belongs_to :user
+end

front-api/models/user.rb

@@ -1,5 +1,9 @@
 class User < ActiveRecord::Base
   has_many :carts
+  has_many :children
+
+  accepts_nested_attributes_for :children
+
   has_secure_password
   validates_presence_of :first_name, :last_name, :password, :email, :password_confirmation