Ok, I think I have a clearer picture. First realize you are not doing anything wrong. It is just that Charlie hasn't been taught certain behaviors that will permit you to take anything from him.

Resource guarding is a normal canine behavior. Those who don't have this issue are lucky or have trained their dogs to know how to give on command! It is annoying to humans, especially if we think of our pet dogs on a human term. How dare our kid not give up his prize toy or treat when we ask for it! The only problem is your dog is displaying NORMAL behavior and you need to accept it and train the dog differently. This is called classical conditioning.

Until the dog is trained (and after), don't make this a bigger deal than it needs to be. I am saying it doesn't have to be a major issue if the dog holds a chewie for longer than we want him too. He isn't holding it to make you angry. He is holding it (guarding it) because that is what dogs (decendants of the wolf) do. In the mean time, don't supply things that you know will trigger a confrontation. If the dog has something you don't want him to have, you need to make something else more appealing to him or leave him have it.

You wonder why is this happening all of a sudden? LuLu's arrival has more than likely kicked this natural guarding instinct into gear. Remember, Charlie didn't have a need to guard his possessions before she came along because he was the only furkid in the house. Now he has someone he thinks may value his possession as much as he does. Again... normal dog behavior.

So how do you deal with it? You need to teach him not to guard his possessions and to reward him for doing other things. In other words....training, more training and even more training! Your goal is to make your dog understand that the approach of a human to his food, toys, space, etc. is a good thing. Your dog needs to think that you approaching him when he has a prized possession means better prizes are on there way!

Teach your dog to GIVE. Start out with possessions he does not value a lot and treats that are highly valued (the better the treat the faster the training will go). Then gradually work your way up to possessions that he cares a whole lot about. Ask him to give the object, then either wait for him to do so (if he knows the cue) or cause him to do so by presenting food near his mouth. Reward and praise him immediately for dropping the possession. Give it back to him as soon as he's done chewing. repeat this, giving the resource back each time. This will help Charlie understand that giving away his resources to you is a good thing, so there's no reason to guard them.

Condition your dog to expect good things when you approach. Especially if he has some sort of highly prized resource, like a bone or chewie. Start slowly with something he does not guard. Walk over, show him the treat while he's enjoying his low value toy or food, and leave. Do this several time throughout the day. Repeat this with low value possessions for several days until he begins to look up at you, with a "Yea, I'm gonna get a treat" expression on his face. Still using a low value possession, take the possessiony from him, saying "give" first. Immediately pop a high value treat in his mouth and return the possession to him. Over a period of weeks or more, gradually move up to repeating the above with higher and higher valued possessions. Remember to keep your safety in mind. NEVER progress faster than your dog is happily willing to go. If the dog is not relaxed and happy at any stage, you have moved too fast. Back off and start over again. When you are working with higher valued possessions, start by only getting as close as the dogs comfort range will tolerate. If he growls or starts guarding, you have gotten to his trigger point and you've gone far enough. Just drop the treat near him. Move closer as the days go by if the dog is ready. Repeat this entire process with several high value objects. When the dog is ready use the "give" command to actually remove the possession from his grip. Remember to always give the object back. Eventually, you will be able to take anything from him.

Best wishes and let us know how it goes!