Hi All- I am looking for some advice. We have a Rough Collie Pup that is 4 months old. Up until recently she has been very good, just the usual puppy nipping etc. She has started being aggressive at feeding time, jumping, barking, yipping and she will not listen to any commands, sit, settle, stay. No way. She is not having any of it she just wants her food. She was also a slow eater now she is GULPING her food down so fast. We can't seem to control her and yelling at her makes it worse, she then starts to bite harder and jump and yip more. ANY advice would be so appreciated. We love her dearly and just want her to be a good dog.