Changing which Category a Product Family belongs to is easy.

It is easy because it is also low impact - it won't affect the capacities of your Product Families and Product Lines.

here is what we're doing in graphical terms

(though for this we don't actually use drag and drop)

  1. Visit the Product Family you want to modify.
  2. Click on the Category dropdown.
  3. Move it to the Category of your choice:

See Also

changing a Product Lines PF 

changing an Item's Product Line