When you look down at your brand new, small and tender puppy peacefully sleeping in its little bed, it's hard to think that in just two to three months it may grow to be 40, 50, or even up to 100 pounds depending on the type of breed. And although its behaviors may cute at the moment, like jumping up and putting his front paws on your body, these actions will be far less enjoyable when your dog is all grown up and literally knocking you over.