I would depend on the temperment of your 3-year old. If your he is well socialized, I wouldn't worry about him accepting a new brother or sister but I would be concerned if the 3-year old doen't play well with other dogs.
In the beginning, the older dog will try to set bounderies with the puppy. As the puppy matures, he/she will challenge the older one but that's just them working out who the alpha dog is. Just keep an eye on them so you can intervene if it gets out of hand.
Good luck and please let us know how it goes! |