I would normally say you should be ok under the conditions you described, but it can happen. Next time you use the TT just take an extra peak at all your water line connections, pump area, etc., look for any suspect moisture.
Also, some folks overlook the exposed exterior plastic grey/black dump valves when they get caught in freezing period, check them as well.
2016 GM 2500HD 6.0L/4.10
2005 Jayco Eagle 278FBS
Reese HP Dual Cam
Putnam Class V