Ability to add specific user to access custom created Sites for the Esri Enterprise Sites Application

[RPGIS]

HI,

I was wondering if it would be possible to add specific users, who have portal accounts, access to Sites that are created from the Esri Enterprise Sites Application. Currently, I am able to have it viewed with team members, members of the organization, or publicly. I would like to be able to specify which users can have access capabilities to this site that are created in the Sites Application in portal, similar to how specific user accounts can be added to certain groups. My goal is to create a site for the department that I am working in and the department may only require specific people to have access to the site.

[Alex_Reid]

We also need a variation of this idea - we need pages within the sites to be sharable to a Group so they can be access controlled for multiple users.

Group A has User A - Site A and Page A

Group B has User B - Site B and Page B

Because I can only share Sites and Pages to Team, Organization, or Public, I have no way of restricted Site A from User B, and vice versa. 

We have 12+ groups who need to be restricted from the 12+ sites associated with each.