User Registration (help please)

Hello,

I need a help please.

I use a plugin called s2Members for membership access to my clients site. This works great for 1 users at a time. My client wishes to allow that registered user to allow other 5 other users to get access to the members pages and posts. So, they are they are sort of a group admin for there own 5 additional registrations.

Is there a plugin that you can think would help me here?

What would be great if I could display the additional fields and users on a page.

And I can set the amount additional users they can allow i.e 5 or 6.

The last part of this goal is that I would like users to be emailed (registees and admins) so custom templates would be great.

Tall order i know, but if you can help that would be great.

Thanks
Mike