Are tents allowed on rv sites?

Yes they are. No additional cost.

If I am not mistaken I believe you can pitch up a tent near the RV if that's what you mean, I remember when my brother in law had an RV , we are a huge family so we pitched up our pop up tent and they never gave us a problem. If you want, call either the Dearborn Civic center or the actual Camp Dearborn number and see just to confirm if you are able to do so, best of luck!!