Wile it is OK to leave it on. I WOULD NOT because if from some reason some water is accidently turn on wile towing you could have a real problem. My friend left his cat in the 5er while towing and somehow the cat turn on the kitchen water and the sink overflowed because the stopper was in the sink and the water ended up on the kitchen floor. The pump emptied the freshwater tank.
It only takes a few seconds to turn on the pump when you stop. Depending on the age of the children you can teach them to turn it on and off at each stop.
