To reproduce this you need to configure your wiki in multilanguage mode, let's say with EN and FR and EN as default language.
Then create a page with both EN and FR language versions. The content of this page should include a link to a child page.
Create the child page by clicking on the link and enter EN and FR language versions of the page.
Rename the child page. The link to the child page will be updated in the EN language version but not in the FR language version of the main page.