I really need help with this. I have a cavalier king charles and he's 8 years old. The stealing kind of suddenly started a few months ago. When he was younger he would steal the odd sock that fell to the floor (very rarely though) and he would always give it back without a problem. But now he will steal anything from shoes, towels, shopping bags to basically anything he can touch. When we try to take the stuff from him he gets really aggressive - growling and snapping. He has never done this before so I really have no idea why he does it. He has plenty of toys and gets walked everyday but nothing will stop him stealing. We can't just move everything because he will just find a way to take something else. Can someone please help with this problem?