Timber loves to attempt to eat anything and particuarly tin foil type things. Today she ate a big bit of tin foil that was tying in the park. I noticed that she was chewing it in her mouth and when i attempted to ge it out, she started growling and trying to bite my hand off and she got sooo defensive. Now she is a little bit like this, really over protective of some of her things, but she has loads of toys and we let her do what she wants in the garden and she never really attempts to bite that badly, well not me anyway lol, but she was really bad about this. Any tips?