To bring a new dog into this situation is just asking for trouble.
I very much doubt if `Buddy` will be very happy about another dog coming into his territory, especially as he is obviously very pampered by your b/f and could lead to him defending his status with aggression towards a new dog.
Its not a simple matter to bring a new dog into a household where an older dog has been the centre of his owners world for years and also its not a very kind thing to do.
WE do not know anything about Buddy eg: his temperament and how he reacts with other dogs, so WE can only give guesses based on the few facts you have posted.
Source(s): GSD owner for 58 years. UK