Soft Delete error while restoring related models with cascade_delete = true

[mayismile]

I have the model User with HasOne relations Profile and Balance. Both of these relations have

'cascade_delete' = true

Deleting runs good, but restoring User model and both related models throws an error Call to a member function restore() on a non-object in a /packages/orm/classes/model/soft.php line 240

The code is

public function restore($cascade_restore = null)
{
    $deleted_column = static::soft_delete_property('deleted_field', static::$_default_field_name);
    $this->{$deleted_column} = null;

    //Loop through all relations and delete if we are cascading.
    $this->freeze();
    foreach ($this->relations() as $rel_name => $rel)
    {
        //get the cascade delete status
        $rel_cascade = is_null($cascade_restore) ? $rel->cascade_delete : (bool)$cascade_restore;

        //Make sure that the other model is soft delete too
        if ($rel_cascade)
        {
            if (! is_subclass_of($rel->model_to, 'Orm\Model_Soft'))
            {
                //Throw if other is not soft
                throw new RelationNotSoft('Both sides of the relation must be subclasses of Model_Soft if cascade delete is true');
            }

            if (get_class($rel) != 'Orm\ManyMany')
            {
                $model_to = $rel->model_to;
                $model_to::disable_filter();

                //Loop through and call restore on all the models
                foreach ($rel->get($this) as $model)
                {
                    $model->restore($cascade_restore); // I checked and this var $model is null
                }

                $model_to::find_deleted($this->{$rel->key_from[0]})->restore($cascade_restore);

                $model_to::enable_filter();
            }
        }
    }
    $this->unfreeze();;

    return $this->save();
}

So, may be I'm wrong with this point, but I changed this code part

//Loop through and call restore on all the models
foreach ($rel->get($this) as $model)
{
    $model->restore($cascade_restore); // I checked and this var $model is null
}

to this one

$model_to::find_deleted($this->{$rel->key_from[0]})->restore($cascade_restore);

and everything started to work fine.

May be I used Soft Delete wrongly?

Thanks