Thank you. That's the only thing I could think of also. His litter box did have pellets, since I just changed it on Wednesday, but maybe not too little enough to make me realize. The two little boys didn't even realize it this morning as they where playing in the room. I quickly shuffled them out and was just so sad. Was I doing something not right? The boys are asking if they can get another, but I can't have this happen again.