A lot of people say to get the oposite sex of the dog you already have. Female dogs are called bitches for a reason. Although I am a firm believer that you can bring either sex into the household. It's the individual dog. I've had a ton of rescues of both sexes and haven't had an issue with either. I have a feeling you are asking these "IF" questions for a reason and I can't wait to see what happends.