The Grandparents of your pup have a lot to do with your pups size. I try and get a female whos sire was a beast, that trait seems to come from the mothers Father; and allows her to produce larger pups. On my CC Pup his sire and damm were nice dogs both over 125lbs but more importantly to me the damms and sires father were over 130lbs, I think this will equate to a good size pup Rocco is now 4months old and over 50lbs on my vets scale