Being a breeder (of dogs) I can honestly say, yes just let them go at it. Watch that they don't hurt each other and when they growl at each other just tell them no. Growling from dogs is never good. If you can't teach them this at a young age, then they will never learn. They will decide for themselves who's who in your house. Cedar isn't being territorial or agressive.....or shouldn't be at his young age. He is probably just scared of S80. If Sadie isn't jealous of Cedar and she has a good temperment and can put up with a puppy then chances are you won't have to worry about her going after Cedar. If Cedar snaps or growls at her, S80 will probably learn to just walk away from him. But make sure that you teach Cedar that growling and/or biting is not acceptable in your house. We had an 8 yr old pomeranian from the time she was a pup and then got an 11 yr old pomeranian that was a rescue. They never liked each other from day one. They got into a few minor fights over food etc. but they eventually lived in the same house without incident. They just learned to avoid each other. With Cedar being a puppy he'll learn very quickly to like S80. Like I said he is probably just more scared having a new home and a new family and a new BIG sister. And he probably hasn't been properly sociallized with other dogs. Just be happy that its the puppy not liking the adult and not the other way around. Don't keep them seperated all the time because then when you are playing with one of them and the other one is locked away they will start getting jealous. Make sure you spend equal amounts of time with each and try doing activities with both of them at the same time to make them feel equal. Even if it is sitting on your living room floor with a dog on either side of you petting them. It's as simple as that. Feed them both at the same time, let them out at the same time, give them the same treats at the same time, walk them at the same time, etc. Do to one what you are doing to the other so one doesn't feel left out. Have fun with your new puppy and good luck. Don't worry Cedar is still young and with proper training and socialization he will outgrow it. Keep us updated on how he is doing.
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