We usually like having two. When older reaches 5, we get a puppy. Occasionally we have had an overlap of three dogs. Due to family illnesses, we didn’t follow our usual pattern. We just lost our shepherd at age 14 and our 5 year old rottie is now an only dog and doesn’t like it. In the spring, we will be looking for a new pup.
Older dogs can be great to help train the new dogs in routines and they keep each other company.