diff --git a/composer.json b/composer.json
index b4f7625..80134c1 100644
--- a/composer.json
+++ b/composer.json
@@ -23,6 +23,7 @@
         "orchestra/testbench": "^9.0",
         "phpstan/phpstan": "^1.10",
         "phpstan/phpstan-mockery": "^1.1",
+        "phpstan/phpstan-phpunit": "^1.4",
         "phpunit/phpunit": "^11.0",
         "staudenmeir/eloquent-json-relations": "^1.11",
         "staudenmeir/laravel-adjacency-list": "^1.21"
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index 29ccebc..ece647c 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -1,11 +1,14 @@
 includes:
     - ./vendor/larastan/larastan/extension.neon
     - ./vendor/phpstan/phpstan-mockery/extension.neon
+    - ./vendor/phpstan/phpstan-phpunit/extension.neon
+    - ./vendor/phpstan/phpstan-phpunit/rules.neon
 parameters:
-    level: 4
+    level: 5
     paths:
         - src
         - tests
     treatPhpDocTypesAsCertain: false
     ignoreErrors:
         - '#Unsafe usage of new static\(\).#'
+        - '#Parameter \#\d+ \$relations of method Illuminate\\Database\\Eloquent\\Collection<[^>]+\>::load\(\) expects#'
diff --git a/tests/Concatenation/LaravelAdjacencyList/AncestorsTest.php b/tests/Concatenation/LaravelAdjacencyList/AncestorsTest.php
index f5d0c1c..960b710 100644
--- a/tests/Concatenation/LaravelAdjacencyList/AncestorsTest.php
+++ b/tests/Concatenation/LaravelAdjacencyList/AncestorsTest.php
@@ -2,6 +2,7 @@
 
 namespace Tests\Concatenation\LaravelAdjacencyList;
 
+use Illuminate\Database\Eloquent\Relations\Relation;
 use Staudenmeir\EloquentHasManyDeep\HasManyDeep;
 use Tests\Concatenation\LaravelAdjacencyList\Models\User;
 
@@ -65,7 +66,7 @@ public function testEagerLoadingWithHasOneDeep()
     public function testLazyEagerLoading()
     {
         $users = User::all()->load([
-            'ancestorPosts' => fn (HasManyDeep $query) => $query->orderBy('id'),
+            'ancestorPosts' => fn (Relation $query) => $query->getQuery()->orderBy('id'),
         ]);
 
         $this->assertEquals([], $users[0]->ancestorPosts->pluck('id')->all());
diff --git a/tests/Concatenation/LaravelAdjacencyList/BloodlineTest.php b/tests/Concatenation/LaravelAdjacencyList/BloodlineTest.php
index c4a1469..939eb3c 100644
--- a/tests/Concatenation/LaravelAdjacencyList/BloodlineTest.php
+++ b/tests/Concatenation/LaravelAdjacencyList/BloodlineTest.php
@@ -2,6 +2,7 @@
 
 namespace Tests\Concatenation\LaravelAdjacencyList;
 
+use Illuminate\Database\Eloquent\Relations\Relation;
 use Staudenmeir\EloquentHasManyDeep\HasManyDeep;
 use Tests\Concatenation\LaravelAdjacencyList\Models\User;
 
@@ -35,7 +36,7 @@ public function testEagerLoading()
     public function testLazyEagerLoading()
     {
         $users = User::all()->load([
-            'bloodlinePosts' => fn (HasManyDeep $query) => $query->orderBy('id'),
+            'bloodlinePosts' => fn (Relation $query) => $query->getQuery()->orderBy('id'),
         ]);
 
         $this->assertEquals([10, 20, 30, 40, 50, 60, 70, 80], $users[0]->bloodlinePosts->pluck('id')->all());