9 Week Old Puppy Getting Increasingly Aggressive

by Jackie
(Utah)

I've had my female a week and a half now. She ate some of our other dogs weight management food which made her not feel very well. She hadn't eaten much so I mixed a bit of wet food into her regular dog food.That's when the food aggression came out. She bit my boyfriend when he petted her and tried to move the bowl. She didn't snap right away, but is very possessive and growls and snarls. I wondered if it was simply because she hadn't eaten much and was super hungry, but when tested again the next day, she wasn't as violent, but still aggressive. I've hand fed her and tested this when I got her with her regular dry food and there's no aggression what so ever. Only when wet food or special treats are involved. I don't give her treats around our other dog, so that's not where the competition is stemming from. Then just this morning I went to put her out to go to the bathroom and as I picked her up like usual she aggressively growled and tried biting me. She did have a bone before, so I'm wondering if she felt like going out meant no bones? She's done well with training to sit and lay down, hasn't had an accident in the house since she whines when she needs out, even during the night and has since day one. I want to correct this, but am not sure how to correctly approach this one since I've never encountered this aggression in a puppy before. Please help! Kids are involved, so this aggression can't carry on.