I didn't have the garden hose hooked to the trailer, Just the Electric Power cable.
I guess the water in the Fresh water holding tank just heated up from the Summer heat while I was in the Hospital having Kidney Surgery.
I am now draining and flushing the Fresh water tank and sanitizing it, so that we have good water with us when we go camping in a couple of days. It will be so wonderful to get away from the house for a few days! It's been a Long summer without being able to go camping!
Thank you for all of your responses! I learned something new today, so my day wasn't wasted!
Dick