My Oliver is nearly 2 and has been successfully potty trained for about a year now. About 2 weeks ago, he peed on my dirty clothes that were on the floor waiting to go into the wash while I was in the other room. I thought it was a fluke and ignored it since I hadn't caught him right away. Then, the next day, just after I had let him back inside after being out to do his business, he peed all over a book in my office. I yelled at him and shook my bottle with rocks in it at him and put him in his crate for about 20 min and then let him outside again. This seemed to do the trick for about 2 weeks until last night. When I woke up this morning there was a HUGE pee stain all over my down comforter. I had slept right thru it and I usually wake up when he or my other dog ask to go out. Is he being naughty or could there be a medical issue? And if it is just naughtiness, what is causing this now? Any help would be great. Thanks.