Having two blogs on one page (using multiple installations)

I am currently running two separate blogs on two separate installations of WordPress. Both are hosted on the same site; one blog is found in the root of the site (Blog #1), the other is found in a subfolder (Blog #2).

Although I would like to fundamentally keep the two blogs separate for administrative purposes, I wanted to have my top level index.php page include content from both blogs.

My initial thought was to just create a file in Blog #2 that I could just call from within a Blog #1 template using the php include function, hoping that in this way I’d be able to display both areas of content without sacrificing keeping the blogs separate. Of course, because the file in Blog #2 included WordPress template tags, once they were included in the Blog #1 file they were parsed as part of Blog #1’s content, not Blog #2’s.

Does anyone have any suggestions as to how I might go ahead doing this?

Just to be clear: I am not trying to create multiple blogs on one WordPress installation (I know there are lots and lots of posts on this subject). I have two existing blogs with several years’ worth of content that I do not want to combine into a single blog for a variety of reasons. The only thing I want to do is have some content from each blog appear together on the home page only.

Thank you!