Hi FetalDump,
this feature is not supported at the moment by the module itself. I suggest you to use one workaround like this: place the blog module on a parent page called Blogs, then create your Blog and your child blogs, then copy the child blogs' URLs. Now create as many sub-pages as your child blogs each with the exact child blog name. Then set your sub-pages Link type to URL , and insert your child blog's url to the url textbox for each sub-page, matching the corresponding child blog. Now your users will see a blog page with all the blogs listed, if they browse to it they see all the blogs with all the entries, then if they navigate to the sub-pages they can filter entries by the corresponding child blog.
Best regards,
Dario Rossa