You have to consider the fact that if you get a female there is always that chance that they will fight. Typically fight will break out between same sex dogs. I found this out the hard way. I already had a females and a male than kept a female from one of their litters and we never ever had an issue. That was until we decided to add another female to our family/pack. Well she tried to gain the pack leader roll at a very early age which progressively got worse. I tried like hell to convince her that I was the pack leader but she continued to lash out at the other two girls.
Plus with adding another pup you may have issues with jealousy but that can be dealt with if it becomes a problem. Just remember to treat them both equally. Spoil them both the same . .
