I decided I was overthinking it. I created a generic logon page that is used for the Global Website Logon page. So if a user tries to access something that needs authentication they will be redirected to the generic logon page. Upon submission they will be redirected back to the page they wanted to access. If they go through the site and reach the parent page unathenticated they can logon using the form on this page which will redirect them upon submission to it's child pages.