I am trying to add sub-categories to my wordpress page. When I go to 'Manage -> Categories', and add a sub-category, it appears on the category page. However, as soon as I move on it disappears. When I try to add another category, the sub-category is still in the 'Category Parent' pull-down. Also, when I added a category of the same name in the writing/editing post page, it created a category but did not show this anywhere else, including the categories section.
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