diff --git a/library/Icingadb/Model/UnreachableParent.php b/library/Icingadb/Model/UnreachableParent.php
index cf78d39a..7b3e3f45 100644
--- a/library/Icingadb/Model/UnreachableParent.php
+++ b/library/Icingadb/Model/UnreachableParent.php
@@ -5,6 +5,7 @@
 namespace Icinga\Module\Icingadb\Model;
 
 use Icinga\Module\Icingadb\Model\Behavior\ReRoute;
+use Icinga\Module\Icingadb\Model\UnreachableParent\ResultSet;
 use InvalidArgumentException;
 use ipl\Orm\Behavior\Binary;
 use ipl\Orm\Behaviors;
@@ -112,6 +113,8 @@ class UnreachableParent extends DependencyNode
             )
         ));
 
+        $query->setResultSetClass(ResultSet::class);
+
         return $query;
     }
 
diff --git a/library/Icingadb/Model/UnreachableParent/ResultSet.php b/library/Icingadb/Model/UnreachableParent/ResultSet.php
new file mode 100644
index 00000000..d564b4e8
--- /dev/null
+++ b/library/Icingadb/Model/UnreachableParent/ResultSet.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace Icinga\Module\Icingadb\Model\UnreachableParent;
+
+use Icinga\Module\Icingadb\Redis\VolatileStateResults;
+use Traversable;
+
+class ResultSet extends VolatileStateResults
+{
+    protected function yieldTraversable(Traversable $traversable)
+    {
+        $knownIds = [];
+        foreach ($traversable as $value) {
+            if (isset($knownIds[$value->id])) {
+                continue;
+            }
+
+            $knownIds[$value->id] = true;
+
+            yield $value;
+        }
+    }
+}
diff --git a/library/Icingadb/Widget/Detail/ObjectDetail.php b/library/Icingadb/Widget/Detail/ObjectDetail.php
index 5b657425..c4e0a689 100644
--- a/library/Icingadb/Widget/Detail/ObjectDetail.php
+++ b/library/Icingadb/Widget/Detail/ObjectDetail.php
@@ -655,7 +655,6 @@ class ObjectDetail extends BaseHtmlElement
                 'service.host',
                 'service.host.state'
             ])
-            ->setResultSetClass(VolatileStateResults::class)
             ->orderBy([
                 'host.state.severity',
                 'host.state.last_state_change',