Hello! I'm trying to report on Chatter and used Custom Object A as the Primary and "Feed: Custom Object A" as the secondary, but only three fields (out of a total of seven needed) are on Custom Object A; the other fields are from Custom Object C. The Chatter Feed Activity custom report doesn't seem to allow for adding another object (Custom Object C, in this case), though.
Thank you both! @Hannah Recker we actually have coefficient, I'll take the route and see where it gets me. Thanks again.