$(document).ready(function() {

//hide child page
$('#page-list ul li.page_item ul').hide();

//when navigate to a child page show all pages
$('#page-list ul li.current_page_item').parent("ul").show();

//show page list when toggle
$('#page-list ul li.active ul').show();

//show current page's child page
$('#page-list ul li.current_page_item ul').show();

$('#page-list ul li').click(function() {
$(this).addClass("active");
$(this).children('ul'); 
});
 
});