Reduction of amount for siblings implemented

app/Models/Event.php

@@ -37,6 +37,7 @@ use Illuminate\Http\Resources\Json\JsonResource;
  * @property string $registration_link
  * @property boolean $pay_per_day
  * @property boolean $pay_direct
+ * @property boolean $sibling_reduction
  * @property boolean $send_weekly_report
  * @property int $participation_fee_1
  * @property int $participation_fee_2
@@ -73,6 +74,7 @@ class Event extends InstancedModel
         'registration_link',
         'pay_per_day',
         'pay_direct',
+        'sibling_reduction',
         'send_weekly_report',
         'participation_fee_1',
         'participation_fee_2',
@@ -104,6 +106,8 @@ class Event extends InstancedModel
         'support_per_person' => AmountCast::class,
         'support_flat' => AmountCast::class,
         'total_max_amount' => AmountCast::class,
+
+        'sibling_reduction' => 'boolean',
     ];
 
     public function tenant(): BelongsTo