It turned out there was a nest of Rats in the compost pile. They were getting into my garage for sure since it was located nest to the garage door. When we discovered them we were able to take out 5 of them with a compost fork and shovel. Nothing like impaling rats with your in-laws ^_^ The same night we set out 14 rat traps and got 3 more rats. I've been putting the traps out every night and got a couple nibbles but no hits. I was thinking about opening that gate up to my Rott Duke. I'm sure they would drive him nuts.