This post shows up here because it is part of the child category that falls under the parent category.
Category: Parent Category
Child Two
This post shows up here because it is part of the child category that falls under the parent category.
Child One
This post shows up here because it is part of the child category that falls under the parent category.
Parent Post
This post shows up here because it is part of the parent category. When viewing the parent category, all post from the parent category and the child category will be displayed.
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