I've had zoe for a couple of months now and my 10 year old collie is not happy with her at all. She tolerates her but guards her own food dish now - prior to this she has always been a picky eater and has been underweight. I had tried everything to get her to put on weight and then we got Zoe. She's probably put on 5-10 lbs. I just try to correct her when she growls and remember to be fair to her when the pup is being annoying as puppys can be. Also, I try to walk with them together every night. I swear that helps. I did have a trainer here the other day and he said that when getting a new puppy, you should board the older dog for 10 days and that will give the puppy a chance to bond with you but that suggestion came too late for me. I think things will work out, just be patient and firm with them. Good luck! Theresa