Issue Summary

The Children Display Macro can optionally refer to a specific page to display the children of, by default it refers to the page it is on. When it refers to another page and that page is renamed, it continues to look for the old name and displays an error: "Page Not Found: <the original page name>"

Steps to Reproduce

1. Create a page (page A)
2. Create a second page (page B) as a child of page A
3. On any page, add a Children Display Macro and set the parent page parameter to Page A. Save the page.
4. Open Page A in edit mode and change the title. Save the page.
5. Observe the Children Display Macro, which is now broken

Expected Results

The Children Display Macro continues to refer to the original page

Actual Results

The Macro throws an error

Workaround

Open the page with the Children Display Macro and update the Parent Page parameter to use the new name.