[quote DeathByWalkies]Cockerpoos are known for resource guarding - it's a breed trait that appears in some lines, and comes from the cocker side of the family.
You do need to see a behaviourist - this is a behaviour issue not a training one. It's important to know that dog behaviour (and training) is a completely unregulated industry, so literally anyone can call themselves a behaviourist (or trainer).
For that reason, it's important to get someone who is properly qualified (NB not all qualifications are created equal - yes, this is a complete minefield) such as
apbc.org.uk/find-an-apbc-member/
www.asab.org/ccab-register
If you have good pet insurance, which cover behaviour, they will cover the costs.
In the meantime, try and avoid creating situations where the dog feels the need to guard items - feed the dog in a room alone. Keep the dog out of rooms where you're cooking / eating food / loading the dishwasher (using baby gates) and / or tell the kids accept that if the dog has some food, it now belongs to the dog - in the grand scheme of things, a dog eating some dropped pizza isn't the end of the world. This will meant the dog has fewer opportunities to practice the behaviour and ingrain it further.
Never, ever tell a dog (any dog!) off for growling. It's the last ditch warning they have before you get into a snap and / or bite. If you tell a dog off for growling, you tend to arrive at a situation where the dog doesn't give a warning anymore, but just goes straight for the bite.
You would probably all benefit from learning about dog body language. I've never understood why we all spend so much time talking about dog training, but very little trying to understand what the dog is telling us. Forget everything you thought you knew - a waggy tail isn't always a sign of a happy dog (merely of emotional arousal). This is a good video to start you off - it will help you to recognise the lower level signals where your dog is telling you she's uncomfortable [/quote]
Excellent post