The two circuits have to be in the schematic, either by using a functional block or by just copying the circuitry,
In Xpedition you can either use the "circuit move and copy" command for pre VX releases (found in the "Edit" menu) . IN Vx you just select what you want to copy (parts, traces, etc), click the Right Mouse Button and select Copy. The software will look for an identical circuit and copies it.
You can find Help in the manuals, available under the "Help" menu.
If I remember well, there was a previous question about this topic also.
Thanks so much. That turned out to be much easier than I thought. I had a little trouble actually pasting the copied circuit into where it was supposed to go (“…. Immovable metal… “messages) but I played with it for about an hour and got the hang of it.