Page permalinks

I am using WordPress as a CMS for a site of mine, creating Pages for the content.

Everything is working great, except for one thing: I have multiple Pages with the same title and Page slug, but with different Page parents; they are, however, both displaying when I try to view the pages via either permalink.

So, let’s say I have the Pages hi and hello, both of which have a child Page yay. When I go to either http://site.com/hi/yay or http://site.com/hello/yay, the content of both Pages are showing up.

Is there a fix for this? I could always just change the Page slugs, but if possible I would really like to make this work the way I wanted to originally.

Thanks!

(I didn’t provide a link to the site I’m working on because I’ve removed the second Page temporarily, until I can find a fix for this.)