Private Parent Pages

am creating some help pages for new bloggers on my blog to give them information to get them up and running quickly. These pages are meant to be private and visible only to contributing bloggers. My top-level page is “WordPress Technical.” I tried to put a “Mobile Plugins” page under the WordPress Technical page, but it did not show up as an option.
As an experiment, I changed WordPress Technical to “Public,” and it showed up as an option as a parent page. So I specified it as a parent page for Mobile Plugins. Worked fine. Then I changed WordPress Technical to “private” again, thinking that it would still “stick” as a parent page. But it didn’t. The child page was simply left orphaned.

Is this a bug or an intentional “feature”?

If it’s a feature, I’d wager that no one would complain if it were left out. ??