What I am trying to do is to get all of the categories that belong to products in a given category. Given the brand category Nike, I want to display the categories that products in Nike also belong too. For instance, in the category Nike there are products that also belong to the categories: Shoes, Shirts, Shocks etc. I want to display a list of these categories.
I have seen many many ways to display the subcategories and subcategories of a parent category. But I am unsure of how to get the categories that each product belongs to for a given category.
Any help or guidance is appreciated.