public function getPivotFields($obj, $prop)
    {
        $reflection = new \ReflectionClass($obj);
        $property = $reflection->getProperty($prop);
        $property->setAccessible(true);
        $value = $property->getValue($obj);
        $property->setAccessible(false);
        
        /* Remove timestamp from pivot */
        return array_diff($value, [
            'deleted_at',
            'created_at',
            'updated_at'
        ]);
    }