Cane Corso are not one of the breeds that do well if left alone all day. When your dog is a puppy, it is even worse. Yes, this will affect her training. If you do not have someone come in and walk her during the day in her formative first months in your home, she is more likely to become neurotic. Do you leave your other dog alone in the house during the day? Your puppy is going to be a lot happier if she can be in a kennel with the other dog, and then when she gets a little older, they can be loose in the house together.