Similar story for me. My entire Harry Potter first editions, some of which I bought literally at midnight in the queue. I was led to believe they were still at a parents house, and so when I moved house a couple of boxes that I guess were misplaced during the move were left in a slightly damp garage. Fast forward to another house move a couple of months ago and I found the, completely destroyed and rotten. The whole time I thought they were back at a parents house.
I'm actually deeply upset about it.