public function action_index3()
{
$view = View::factory('view1');
$view ->set('name','Tokyo');
$view ->set('age','1980');
$subview = View::factory('view2');
$subview->set('meow', 'woof');
$view ->set('subview', $subview);
$this->response->body($view);
}
Then just echo $subview in your view.