Pages: content disappears on sidebar move

Hello guys!

I’m creating my own theme, based on the code of ‘earthling’, and I’m playing around with ‘page.php’.

The trouble is, when I move <?php get_sidebar(); ?> above “the loop” <?php if (have_posts()) :?> down to <?php endif; ?>) then the content of that page disappears and my blog appears.

If I leave the sidebar-calling till after “the loop” then my page doesn’t sit right as the sidebar waits until after the page has finished before appearing. There might still be an example at https://www.heebie.co.uk/wordpress/about/

Can anyone help?