Currently there is no a way to add relationship to a profile on submission. Meaning when someone submits a new profile that a relationship be attached to that contact.
This question outlines how it can be done via API How to use API chaining to create a contact and a relationship
In the case I currently need it for WP is the CMS, so I would be seeking something that is CMS independent, the Drupal modules wouldn't work.
What is needed to be done so that there is an option in the settings of the profile to create a relationship. Has anyone done any work like this or have any ideas on what makes sense to look at for something be developed?