the tag <?php wp_list_pages('depth=2&sort_column=menu_order&title_li=&child_of='. $parent_id); ?> inside SidebarTemplate makes a listing of 2 levels (pages&Subpages) of Pages in the sidebar.
What I really wanted is to show a listing of +2 levels of Pages in the Sidebar, counting from present Page. That is, the List would include Current Page, Parent Page and it's recursive Parents and 2 levels of siblings.
If this could be done for any number i then even better!