A couple of issues come to mind with the setup:
You need to determine the towing capacity of the Class B you want and the weight of the TT you plan to get. This is the only way you'll know if the Class B has the capacity to tow the TT safely.
Campgrounds usually only allow one RV per campsite. You'll need to find two sites together which can be difficult during busy season.
I don't know your family dynamics. If I planned to travel with a family I would consider a toyhauler type trailer either bumper pull or 5th wheel. The garage area will carry all the extras and provides a flexible space once you are at a campsite. Bedroom, class room, entertainment area, dining area,....etc.
For a tow vehicle a suburban/navigator or full size van for the bumper pull. For the 5th wheel a CrewCab Dually truck or regular cab pickup and car/minivan driven separately to provide space for everyone.
