diff --git a/app/models/comment.rb b/app/models/comment.rb
index f1158bd4e..a2973cf22 100644
--- a/app/models/comment.rb
+++ b/app/models/comment.rb
@@ -1,5 +1,5 @@
 class Comment < ActiveRecord::Base
-  validate :validate_creator_is_not_limited
+  validate :validate_creator_is_not_limited, :on => :create
   validates_format_of :body, :with => /\S/, :message => 'has no content'
   belongs_to :post
   belongs_to :creator, :class_name => "User"
@@ -101,16 +101,19 @@ class Comment < ActiveRecord::Base
     end
   end
 
-  def update_last_commented_at_on_destroy
-    if Comment.where("post_id = ? and id <> ?", post_id, id).count == 0
-      Post.update_all("last_commented_at = NULL", ["id = ?", post_id])
+  def update_last_commented_at_on_create
+    if Comment.where("post_id = ?", post_id).count <= Danbooru.config.comment_threshold && !do_not_bump_post?
+      Post.update_all(["last_commented_at = ?", created_at], ["id = ?", post_id])
     end
     true
   end
 
-  def update_last_commented_at_on_create
-    if Comment.where("post_id = ?", post_id).count <= Danbooru.config.comment_threshold && !do_not_bump_post?
-      Post.update_all(["last_commented_at = ?", created_at], ["id = ?", post_id])
+  def update_last_commented_at_on_destroy
+    other_comments = Comment.where("post_id = ? and id <> ?", post_id, id).order("id DESC")
+    if other_comments.count == 0
+      Post.update_all("last_commented_at = NULL", ["id = ?", post_id])
+    else
+      Post.update_all(["last_commented_at = ?", other_comments.first.created_at], ["id = ?", post_id])
     end
     true
   end