If sandbox/page.mdwn has been generated and sandbox/sidebar.mdwn is created, the sidebar is only added to sandbox and none of the subpages. --TaylorKillian

Yes, a known bug. As noted in the code: --Joey

# FIXME: This isn't quite right; it won't take into account
# adding a new sidebar page. So adding such a page
# currently requires a wiki rebuild.
add_depends($page, $sidebar_page);