These are good points. When I was younger we usually only had one dog at a time. When I got cody(gsd) we did have a 12 year old dog that got along well with him. My daughter had gotten Clippper, Cody's litter mate. They were raised in separate homes till Clipper was a little over a year old. She used to bring him over all the time and they were always glad to see each other. Then she moved out of state and Clipper came to his forever home with me and Cody. I think they got along so well was because previously they had been raised separate. They were best buddies here. I think about getting 2 puppies, I miss my gsds and how they were, but this article does make me rethink it! I have Hooch the little pittbull, and though I REALLY want another gsd or collie I think he is best as an only dog, at least for now. It's only been 7 months that he has been the only dog here with me. I also "worry" if I wait till I retire in a few years that getting a couple pups would all mean geriatric dogs when I'm getting up there too!