Sidebar help

Hi there,

I need to have a sidebar that recurs throughout a whole section. Basically I have sidebar that has been specifically made for the blog section, and I have called it, sidebar-blog.php however this sidebar only appears when the user is at /blog, however I need to show when the user is reading a blog post, or looking through the archives, or looking through the blog categories, basically I need to show it whatever the page aslong as that page is to do with the blog.