diff --git a/application/controllers/api/v1/Admins_api_v1.php b/application/controllers/api/v1/Admins_api_v1.php
index 20a22bb6..12d79150 100644
--- a/application/controllers/api/v1/Admins_api_v1.php
+++ b/application/controllers/api/v1/Admins_api_v1.php
@@ -52,7 +52,7 @@ class Admins_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
 
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $admins = empty($keyword)
                 ? $this->admins_model->get(NULL, $limit, $offset, $order_by)
@@ -67,9 +67,9 @@ class Admins_api_v1 extends EA_Controller {
                     $this->admins_model->only($admin, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->admins_model->attach($admin, $attach);
+                    $this->admins_model->load($admin, $with);
                 }
             }
 
@@ -92,7 +92,7 @@ class Admins_api_v1 extends EA_Controller {
         {
             $fields = $this->api->request_fields();
 
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $admin = $this->admins_model->find($id);
 
@@ -103,9 +103,9 @@ class Admins_api_v1 extends EA_Controller {
                 $this->admins_model->only($admin, $fields);
             }
 
-            if ( ! empty($attach))
+            if ( ! empty($with))
             {
-                $this->admins_model->attach($admin, $attach);
+                $this->admins_model->load($admin, $with);
             }
 
             if ( ! $admin)
diff --git a/application/controllers/api/v1/Appointments_api_v1.php b/application/controllers/api/v1/Appointments_api_v1.php
index 06f12afd..0758b799 100644
--- a/application/controllers/api/v1/Appointments_api_v1.php
+++ b/application/controllers/api/v1/Appointments_api_v1.php
@@ -58,7 +58,7 @@ class Appointments_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
 
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $appointments = empty($keyword)
                 ? $this->appointments_model->get(NULL, $limit, $offset, $order_by)
@@ -75,9 +75,9 @@ class Appointments_api_v1 extends EA_Controller {
                     $this->appointments_model->only($appointment, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->appointments_model->attach($appointment, $attach);
+                    $this->appointments_model->load($appointment, $with);
                 }
             }
 
@@ -100,7 +100,7 @@ class Appointments_api_v1 extends EA_Controller {
         {
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $appointment = $this->appointments_model->find($id);
 
@@ -111,9 +111,9 @@ class Appointments_api_v1 extends EA_Controller {
                 $this->appointments_model->only($appointment, $fields);
             }
 
-            if ( ! empty($attach))
+            if ( ! empty($with))
             {
-                $this->appointments_model->attach($appointment, $attach);
+                $this->appointments_model->load($appointment, $with);
             }
 
             if ( ! $appointment)
diff --git a/application/controllers/api/v1/Categories_api_v1.php b/application/controllers/api/v1/Categories_api_v1.php
index 2fb5b15c..5d4152db 100644
--- a/application/controllers/api/v1/Categories_api_v1.php
+++ b/application/controllers/api/v1/Categories_api_v1.php
@@ -52,7 +52,7 @@ class Categories_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $service_categories = empty($keyword)
                 ? $this->service_categories_model->get(NULL, $limit, $offset, $order_by)
@@ -67,9 +67,9 @@ class Categories_api_v1 extends EA_Controller {
                     $this->service_categories_model->only($service_category, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->service_categories_model->attach($service_category, $attach);
+                    $this->service_categories_model->load($service_category, $with);
                 }
             }
 
@@ -92,7 +92,7 @@ class Categories_api_v1 extends EA_Controller {
         {
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $service_category = $this->service_categories_model->find($id);
 
@@ -103,9 +103,9 @@ class Categories_api_v1 extends EA_Controller {
                 $this->service_categories_model->only($service_category, $fields);
             }
 
-            if ( ! empty($attach))
+            if ( ! empty($with))
             {
-                $this->service_categories_model->attach($service_category, $attach);
+                $this->service_categories_model->load($service_category, $with);
             }
 
             if ( ! $service_category)
diff --git a/application/controllers/api/v1/Customers_api_v1.php b/application/controllers/api/v1/Customers_api_v1.php
index ab1c51aa..98e3aa5c 100644
--- a/application/controllers/api/v1/Customers_api_v1.php
+++ b/application/controllers/api/v1/Customers_api_v1.php
@@ -52,7 +52,7 @@ class Customers_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
 
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $customers = empty($keyword)
                 ? $this->customers_model->get(NULL, $limit, $offset, $order_by)
@@ -67,9 +67,9 @@ class Customers_api_v1 extends EA_Controller {
                     $this->customers_model->only($customer, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->customers_model->attach($customer, $attach);
+                    $this->customers_model->load($customer, $with);
                 }
             }
 
diff --git a/application/controllers/api/v1/Providers_api_v1.php b/application/controllers/api/v1/Providers_api_v1.php
index d030827a..c5ba3b8c 100644
--- a/application/controllers/api/v1/Providers_api_v1.php
+++ b/application/controllers/api/v1/Providers_api_v1.php
@@ -52,7 +52,7 @@ class Providers_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $providers = empty($keyword)
                 ? $this->providers_model->get(NULL, $limit, $offset, $order_by)
@@ -67,9 +67,9 @@ class Providers_api_v1 extends EA_Controller {
                     $this->providers_model->only($provider, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->providers_model->attach($provider, $attach);
+                    $this->providers_model->load($provider, $with);
                 }
             }
 
@@ -92,7 +92,7 @@ class Providers_api_v1 extends EA_Controller {
         {
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $provider = $this->providers_model->find($id);
 
@@ -103,9 +103,9 @@ class Providers_api_v1 extends EA_Controller {
                 $this->providers_model->only($provider, $fields);
             }
 
-            if ( ! empty($attach))
+            if ( ! empty($with))
             {
-                $this->providers_model->attach($provider, $attach);
+                $this->providers_model->load($provider, $with);
             }
 
             if ( ! $provider)
diff --git a/application/controllers/api/v1/Secretaries_api_v1.php b/application/controllers/api/v1/Secretaries_api_v1.php
index c5acbf03..c2e4ca16 100644
--- a/application/controllers/api/v1/Secretaries_api_v1.php
+++ b/application/controllers/api/v1/Secretaries_api_v1.php
@@ -52,7 +52,7 @@ class Secretaries_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $secretaries = empty($keyword)
                 ? $this->secretaries_model->get(NULL, $limit, $offset, $order_by)
@@ -67,9 +67,9 @@ class Secretaries_api_v1 extends EA_Controller {
                     $this->secretaries_model->only($secretary, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->secretaries_model->attach($secretary, $attach);
+                    $this->secretaries_model->load($secretary, $with);
                 }
             }
 
diff --git a/application/controllers/api/v1/Services_api_v1.php b/application/controllers/api/v1/Services_api_v1.php
index 8b9f6d49..b9d0b18e 100644
--- a/application/controllers/api/v1/Services_api_v1.php
+++ b/application/controllers/api/v1/Services_api_v1.php
@@ -52,7 +52,7 @@ class Services_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $services = empty($keyword)
                 ? $this->services_model->get(NULL, $limit, $offset, $order_by)
@@ -67,9 +67,9 @@ class Services_api_v1 extends EA_Controller {
                     $this->services_model->only($service, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->services_model->attach($service, $attach);
+                    $this->services_model->load($service, $with);
                 }
             }
 
@@ -92,7 +92,7 @@ class Services_api_v1 extends EA_Controller {
         {
             $fields = $this->api->request_fields();
             
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $service = $this->services_model->find($id);
 
@@ -103,9 +103,9 @@ class Services_api_v1 extends EA_Controller {
                 $this->services_model->only($service, $fields);
             }
             
-            if ( ! empty($attach))
+            if ( ! empty($with))
             {
-                $this->services_model->attach($service, $attach);
+                $this->services_model->load($service, $with);
             }
 
             if ( ! $service)
diff --git a/application/controllers/api/v1/Unavailabilities_api_v1.php b/application/controllers/api/v1/Unavailabilities_api_v1.php
index 6578b36e..b5769287 100644
--- a/application/controllers/api/v1/Unavailabilities_api_v1.php
+++ b/application/controllers/api/v1/Unavailabilities_api_v1.php
@@ -52,7 +52,7 @@ class Unavailabilities_api_v1 extends EA_Controller {
 
             $fields = $this->api->request_fields();
 
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $unavailabilities = empty($keyword)
                 ? $this->unavailabilities_model->get(NULL, $limit, $offset, $order_by)
@@ -67,9 +67,9 @@ class Unavailabilities_api_v1 extends EA_Controller {
                     $this->unavailabilities_model->only($unavailability, $fields);
                 }
 
-                if ( ! empty($attach))
+                if ( ! empty($with))
                 {
-                    $this->unavailabilities_model->attach($unavailability, $attach);
+                    $this->unavailabilities_model->load($unavailability, $with);
                 }
             }
 
@@ -92,7 +92,7 @@ class Unavailabilities_api_v1 extends EA_Controller {
         {
             $fields = $this->api->request_fields();
 
-            $attach = $this->api->request_attach();
+            $with = $this->api->request_with();
 
             $unavailability = $this->unavailabilities_model->find($id);
 
@@ -103,9 +103,9 @@ class Unavailabilities_api_v1 extends EA_Controller {
                 $this->unavailabilities_model->only($unavailability, $fields);
             }
 
-            if ( ! empty($attach))
+            if ( ! empty($with))
             {
-                $this->unavailabilities_model->attach($unavailability, $attach);
+                $this->unavailabilities_model->load($unavailability, $with);
             }
 
             if ( ! $unavailability)
diff --git a/application/libraries/Api.php b/application/libraries/Api.php
index 299ed320..49c9e0f3 100644
--- a/application/libraries/Api.php
+++ b/application/libraries/Api.php
@@ -281,19 +281,19 @@ class Api {
     }
 
     /**
-     * Get the provided "attach" array of the current request.
+     * Get the provided "with" array of the current request.
      *
      * @return array|null
      */
-    public function request_attach(): ?array
+    public function request_with(): ?array
     {
-        $attach = request('attach');
+        $with = request('with');
 
-        if ( ! $attach)
+        if ( ! $with)
         {
             return NULL;
         }
 
-        return array_map('trim', explode(',', $attach));
+        return array_map('trim', explode(',', $with));
     }
 }