Eh everyone's going to have different experiences. I've done three puppies at once and then two at once several times thru fostering. It really depends on how much time and supervision you have to offer. Puppies need short bursts of training everyday. With two puppies you need the time to train each of them separately. It's also possible that they may bond more to each other than to your family. When one regresses with house breaking, chances are the other will too. Is it doable? Yes but you need to be prepared. Not to mention two puppies means twice as much at the vet between immunizations, heartworm prevention, flea and tick prevention and eventually spaying and neutering.