I forgot to mention, there are two outlets in the laundry room and neither had a GFCI. The one on the left was an end run, while the one on the right was a line/load. It seemed logical to assume the one on the left was the load for the other one, right? Nope. They were both on separate circuits. So I had to buy
two GFCI outlets.
Turns out the only load on the right outlet was the ceiling lights. There is a lot of screwy electrical work in this house. While trying to identify the breakers, I discovered 5 outlets that were wired backwards, including the one by the washer.