19kg is about 41lbs. I've won many bets with people just looking at dogs and guessing their weights but of course not for money or beer just a friendly bet. The black dog on top is Manny. He was 40 lbs at 8 months. Not sure how much more he grew. And the red/white head female is a sister to Head strong. You could see the difference in size between the two litter. I also like mine to be 30-40 lbs also. Anything bigger than that then they gotta go. Smaller dogs=less food to feed and easier to handle.