I've set up a site (http://www.nightingaleandmetcalf.com/hello/) which uses some manually coded links in the menu to show different posts. So links in the menu go to /?cat=3 or /?cat=7.
/?cat=7 works fine and just shows the posts with 'Research' as a category but /?cat=3 shows all the posts even those without 'Previous Commissions' as a category.
I'm stumped as to why this is happening as I've used this same technique on another site and it worked fine.
Does anyone have any ideas?