This thread is resolved. Here is a description of the problem and solution.
Problem:
The client is trying to translate three child pages, but after translation, they all incorrectly have 'parent-a' as their parent instead of 'parent-b'. This issue occurs only in the secondary language.
Solution:
First, ensure you have a backup of your site. Then, we recommend trying the workaround suggested in a related support ticket, which you can find here: WPML support forum post.
Additionally, navigate to WPML>>Settings and verify that the 'Posts and pages synchronization' options are enabled, especially the 'Set page parent for translation according to page parent of the original language' option.
If this solution does not resolve your issue or seems outdated, please check related known issues at https://wpml.org/known-issues/, verify the version of the permanent fix, and confirm that you have installed the latest versions of themes and plugins. We highly recommend opening a new support ticket if the problem persists. You can do so here: WPML support forum.
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