diff --git a/app/services/post_alerter.rb b/app/services/post_alerter.rb
index 7a4580ad189..ea1b8105903 100644
--- a/app/services/post_alerter.rb
+++ b/app/services/post_alerter.rb
@@ -261,6 +261,7 @@ class PostAlerter
   end
 
   def should_notify_previous?(user, post, notification, opts)
+    return false unless notification
     case notification.notification_type
     when Notification.types[:edited] then should_notify_edit?(notification, post, opts)
     when Notification.types[:liked]  then should_notify_like?(user, notification)
@@ -330,7 +331,7 @@ class PostAlerter
     # Don't notify the same user about the same type of notification on the same post
     existing_notification_of_same_type = existing_notifications.find { |n| n.notification_type == type }
 
-    return if existing_notification_of_same_type && !should_notify_previous?(user, post, existing_notification_of_same_type, opts)
+    return if existing_notifications.present? && !should_notify_previous?(user, post, existing_notification_of_same_type, opts)
 
     notification_data = {}
 
diff --git a/spec/services/post_alerter_spec.rb b/spec/services/post_alerter_spec.rb
index 301f16fadd0..4a73313c7b1 100644
--- a/spec/services/post_alerter_spec.rb
+++ b/spec/services/post_alerter_spec.rb
@@ -165,9 +165,11 @@ describe PostAlerter do
   end
 
   context 'quotes' do
+    let(:category) { Fabricate(:category) }
+    let(:topic) { Fabricate(:topic, category: category) }
 
     it 'does not notify for muted users' do
-      post = Fabricate(:post, raw: '[quote="EvilTrout, post:1"]whatup[/quote]')
+      post = Fabricate(:post, raw: '[quote="EvilTrout, post:1"]whatup[/quote]', topic: topic)
       MutedUser.create!(user_id: evil_trout.id, muted_user_id: post.user_id)
 
       expect {
@@ -176,7 +178,7 @@ describe PostAlerter do
     end
 
     it 'does not notify for ignored users' do
-      post = Fabricate(:post, raw: '[quote="EvilTrout, post:1"]whatup[/quote]')
+      post = Fabricate(:post, raw: '[quote="EvilTrout, post:1"]whatup[/quote]', topic: topic)
       IgnoredUser.create!(user_id: evil_trout.id, ignored_user_id: post.user_id)
 
       expect {
@@ -184,9 +186,27 @@ describe PostAlerter do
       }.to change(evil_trout.notifications, :count).by(0)
     end
 
-    it 'does not collapse quote notifications' do
-      topic = Fabricate(:topic)
+    it 'does not notify for users with new reply notification' do
+      post = Fabricate(:post, raw: '[quote="EvilTrout, post:1"]whatup[/quote]', topic: topic)
+      notification = Notification.create!(topic: post.topic,
+                                          post_number: post.post_number,
+                                          read: false,
+                                          notification_type: Notification.types[:replied],
+                                          user: evil_trout,
+                                          data: { topic_title: "test topic" }.to_json
+                                         )
 
+      expect {
+        PostAlerter.post_created(post)
+      }.to change(evil_trout.notifications, :count).by(0)
+
+      notification.destroy
+      expect {
+        PostAlerter.post_created(post)
+      }.to change(evil_trout.notifications, :count).by(1)
+    end
+
+    it 'does not collapse quote notifications' do
       expect {
         2.times do
           create_post_with_alerts(