diff --git a/src/Database/Traits/Multisite.php b/src/Database/Traits/Multisite.php
index 7ea94302d..944e715e4 100644
--- a/src/Database/Traits/Multisite.php
+++ b/src/Database/Traits/Multisite.php
@@ -27,6 +27,7 @@ trait Multisite
      * Set to an array of options for more granular controls:
      *
      * - **sync** - logic to sync specific sites, available options: `all`, `group`, `locale`
+     * - **structure** - enable the sync of tree/sortable structures, default: `true`
      * - **delete** - delete all linked records when any record is deleted, default: `true`
      *
      *     protected $propagatableSync = false;
@@ -355,6 +356,9 @@ public function getMultisiteSyncSites()
      * For example, finding a model using attributes from another site, or finding
      * all connected models for all sites.
      *
+     * If the value is provided as a string, it must be the ID from the primary record,
+     * in other words: taken from `site_root_id` not from the `id` column.
+     *
      * @param \Illuminate\Database\Eloquent\Builder $query
      * @param string|\Illuminate\Database\Eloquent\Model $idOrModel
      * @return \Illuminate\Database\Eloquent\Builder
diff --git a/src/Database/Traits/SimpleTree.php b/src/Database/Traits/SimpleTree.php
index 181525efb..e3a0aaf60 100644
--- a/src/Database/Traits/SimpleTree.php
+++ b/src/Database/Traits/SimpleTree.php
@@ -58,6 +58,15 @@ public function initializeSimpleTree()
             'key' => $this->getParentColumnName(),
             'replicate' => false
         ];
+
+        // Multisite
+        if (
+            $this->isClassInstanceOf(\October\Contracts\Database\MultisiteInterface::class) &&
+            $this->isMultisiteSyncEnabled() &&
+            $this->getMultisiteConfig('structure', true)
+        ) {
+            $this->addPropagatable(['children', 'parent']);
+        }
     }
 
     /**
diff --git a/src/Database/Traits/Sortable.php b/src/Database/Traits/Sortable.php
index 2c274da47..c63d90daa 100644
--- a/src/Database/Traits/Sortable.php
+++ b/src/Database/Traits/Sortable.php
@@ -68,6 +68,16 @@ public function setSortableOrder($itemIds, $referencePool = null)
             throw new Exception('Invalid setSortableOrder call - count of itemIds do not match count of referencePool');
         }
 
+        // Multisite
+        $keyName = $this->getKeyName();
+        if (
+            $this->isClassInstanceOf(\October\Contracts\Database\MultisiteInterface::class) &&
+            $this->isMultisiteSyncEnabled() &&
+            $this->getMultisiteConfig('structure', true)
+        ) {
+            $keyName = 'site_root_id';
+        }
+
         $upsert = [];
         foreach ($itemIds as $id) {
             $sortOrder = $sortKeyMap[$id] ?? null;
@@ -79,7 +89,7 @@ public function setSortableOrder($itemIds, $referencePool = null)
         if ($upsert) {
             foreach ($upsert as $update) {
                 $this->newQuery()
-                    ->where($this->getKeyName(), $update['id'])
+                    ->where($keyName, $update['id'])
                     ->update([$this->getSortOrderColumn() => $update['sort_order']]);
             }
         }
diff --git a/src/Database/TreeCollection.php b/src/Database/TreeCollection.php
index 55ab24501..d67f7e421 100644
--- a/src/Database/TreeCollection.php
+++ b/src/Database/TreeCollection.php
@@ -19,8 +19,24 @@ class TreeCollection extends Collection
      */
     public function toNested($removeOrphans = true)
     {
+        // Multisite
+        $keyMethod = 'getKey';
+        if (
+            ($model = $this->first()) &&
+            $model->isClassInstanceOf(\October\Contracts\Database\MultisiteInterface::class) &&
+            $model->isAttributePropagatable('children') &&
+            $model->isAttributePropagatable('parent')
+        ) {
+            $keyMethod = 'getMultisiteKey';
+        }
+
+        // Get dictionary
+        $collection = [];
+        foreach ($this as $item) {
+            $collection[$item->{$keyMethod}()] = $item;
+        }
+
         // Set new collection for "children" relations
-        $collection = $this->getDictionary();
         foreach ($collection as $key => $model) {
             $model->setRelation('children', new Collection);
         }
@@ -34,10 +50,10 @@ public function toNested($removeOrphans = true)
 
             if (array_key_exists($parentKey, $collection)) {
                 $collection[$parentKey]->children[] = $model;
-                $nestedKeys[] = $model->getKey();
+                $nestedKeys[] = $model->{$keyMethod}();
             }
             elseif ($removeOrphans) {
-                $nestedKeys[] = $model->getKey();
+                $nestedKeys[] = $model->{$keyMethod}();
             }
         }