If you want to tow a popup, buy a vehicle rated to tow at least 3,000 lbs.
Since you haven't purchased the Jeep yet, don't buy anything until you determine what Rev you want to buy. IMHO, a popup can provide the most space at a lower weight. But, if you want a bigger popup that has a toilet/shower combination, the weight starts increasing. And, consider whether you want to be able to carry bicycles or other stuff for the kids.
My suggestion, if the budget allows, find a vehicle rated for around 5,000 lbs. Towing capacity and you will have far more choices for buying a popup or small travel trailer.
We really enjoyed travelling and camping with our two sons when we had our Starstream. It had a 12 foot box, but no toilet or shower. If I were doing it now, I would want a toilet/shower combination.
Good luck in your search....hope you are able to archive your goal.