It's food aggression/ resource guarding. Very common, and when it's directed at humans, especially from a young age, it's easy to fix.
- Hand feed meals.
- When you can't hand feed, feed in a crate, so that she knows there is no competition.
- Teach impulse control for eating - sits and waits for food until you release her. (Here
is my puppy demonstrating)
- Make two bowls of her breakfast or dinner (same serving size, split in two) - add some yummy things to it like yogurt, oils, supplements, canned food - nothing extreme, just to spice it up a bit. Make her sit/wait for one, release her to it. Step away with the second, bend down and slide the second past her and just a little to the side. She'll likely go to that bowl. When she does, take the old bowl up. Repeat. (This is called a trading game- positive associations with you taking things!)
- Walk by her eating loose or in her crate and drop high value (think hotdogs or cheese!) food in her bowl or near her bowl as you pass. She learns "humans near my food bowl = awesome snacks!"
- When you need to take items from her in the house, offer her something else to trade for it. If she has a sock, offer her a chunk of hotdog for it. You don't want resources to ALWAYS be taken away with no reward for giving them up.
If she has something like this and she is cornered (in her crate - dogs are very territorial there!) then lure her out and try to distract, ask for something else first, like you did with the kong - perfect intuition! You traded her for what she had before in a safe manner, you just waited until after she displayed the inappropriate signals that she was uncomfortable first. Do this proactively next time an issue occurs.