Question: Help! I accidentally exited a family. How do I make them Active again?
Answer: If you exited a family accidentally, you can just delete that Exit status from the Family Enrollment History. That will take the family back to the Active Status. If you reactivated them, delete both the top active status and the exit status.
Click on the Family Home link on the left and scroll to the bottom of the page to the Family Enrollment History. You will see the "delete" icon on the right-hand side.

As you can see, if you reactivate the family, this adds a new enrollment date. This will cause errors with your reports.