YuChen

Hi, I currently have 2 dogs, one male and one female. They are both fixed and are siblings. They're both mastiff x rotti mixes and are around 2 and a half years old now. My dog, Happy (F), will become protective over her food and chews. She's not really protective over the toys. The problem is that she exhibits this behaviour towards my other dog, Lucky (M). Not once has she ever done it to me or any of my family members. I could be right next to her and even move her bowl/chews without her growling or barking, but whenever Lucky is even remotely close, she starts letting him know to back off. I do feed them with enough distance between them that she doesn't do this, but whenever she's with a kong or a chew is when this behaviour usually shows up. If Lucky gets too close and does not move, Happy will often pickup whatever she's eating/chewing and move farther away from him after growling/barking. It's ironic sometimes though since she'll go to his bowl after they're done eating to gobble any leftovers and once again become protective if he comes near. There's another situation where something similar happens but I'm not sure if it counts as resource guarding. Often my neighbour's dog will approach the fence (it's a wire fence so they can clearly see each other), and if I give her (neighbour's dog) a treat, Happy becomes upset and will jump at the fence and bark at her. I did read the article on resource guarding, specifically the one about food, but I could not see a section on what to do when it's against other dogs.