I have a Category "Articles" and in there is the Category "Travel". I want to allow a user group to add and edit articles as children of travel, but they should not be able to edit the page travel. How can I do that?
use a different resource group for the Travel and Articles resources.
UPDATE You might have to create a new policy for these users, OR probably the easiest thing to do is to customize the manager form and hide/disable the fields you don't want edited from the groups/users you don't want to have access to. [admin->security->form customization]