Thanks for your input name changes/change requests.
Charles Cawley lists only Spytihněv and Vratislav as the two children of Bořivoj and Ludmila. I have not found any other named children. Ratislav is not a common Czech name, it has been around in Slovakia but mostly in Serbia, probably derived from Rastislav/Rostislav. Given the closeness of Vratislav and Ratislav I would think they are the same and since Ratislav doesn't have any other data or family connections he could be safely merged with Vratislav.