Yes, it is possible. You will need to create a new template file named template-sitemap.php in your child theme directory to replace the one in the parent and copy over the code contents from the parent and it’s referred file /framework/partials/sitemap.php. Or you can simply the edit the file /framework/partials/sitemap.php this way –
Remove the lines 69 to 74 which read like this –
and for excluding the pages, modify the line 60 –
wp_list_pages(array('exclude' => '', 'title_li' => ''));
as per the instructions provided here –
http://codex.wordpress.org/Function_Reference/wp_list_pages#Exclude_Pages_from_List
Hope this helps.