Password protected pages not working for secondary page

This used to work: I had a password-protected page with links to two other password-protected pages. All pages used the same password. The other two pages used the first page as the parent page.

Since updating to WP 3.5.1, now only the first page (parent page) works when the password is entered. If I click on a link on that page, instead of going to the secondary page, I’m taken back out to the “Please enter your password” form page. I enter the password and it just refreshes the form. I can’t get to the second page.

What do I need to do to fix this?

Thanks.