[ASK] Show Parent Page Title

I have problem, friend. I want to show the current parent title and children title in sidebar continuously, based on page active.
Example :
My Page :
Info
>Contact

If i selected Contact, i want to show parent title ‘Info’ too. So, the display like this in the sidebar:

INFO
– Contact

Here is my code :

<?php
	$parent   = get_the_title($post->post_parent);
	$children = wp_list_pages('title_li=&child_of='.$post->ID.'&echo=0');

	if ($children) { ?>
		<?php echo $parent; ?>
		<ul>
			<?php echo $children; ?>
		</ul>
	<?php } ?>

Help me.. please.
Thanks before