[keycloak-user] Identity Brokering Question

Is it possible to set up multiple keycloak realms as an identity broker to a single realm? For example, we have a site that is mutli-tenant and users are in different realms. Each site will connect to realm A, B, or C depending on where the user goes to log in. I want to build a micro-service that is available to serve authenticated requests from all the sites. So, can I set up a realm D that will accept bearer tokens from realms A, B or C? -- Christopher Savory Software Engineer | EdLogics