The most recent SUVs that can tow that TT is a 2006 8.1L Suburban/Yukon XL 2500 with 4.10 axle ratio. No SUVs after 2006. 2000-2006 GM twins 8.1L and 2000-2005 Ford Excursion V10/4.30 or PSD. 1-ton vans also work from that era, again with V10 or 8.1L. They are all quite rare with low mileage.
How far do you expect to travel? If under about 250 miles each way, then taking two vehicles may be worthwhile. Then you can get an HD pickup to tow and whatever your other big family vehicle is, say minivan or smaller SUV.
About how much do all those people weight? More recent 1-ton passenger vans should be comfortable up to around 8000 pounds dry. There are other models with similar floorplans that would work. Unfortunately, receiver and payload limits almost all 2007+ SUVs from towing 7k pound loaded TTs with large families onboard.
