here’s another reason. if you ever have to board them, they won’t notice you’re gone. i’ve boarded one dog, years later 2 dogs together — with one dog, it’s really mad at you for the first couple of days after you get back. with 2 dogs from the same household, seriously, I don’t think they even notice you’re gone — so they’re just plain happy to see you when you get back!
and another. an older dog can teach a younger dog the ropes -can save you a lot of work.
and still another — when an older dog is failing, the younger one looks out for it. my experience. I had 2 dogs for 3 years — best 3 years of my life.