I will be buying my family's first cavalier puppy and the breeder we are working with at the moment has some adorable 14 week old puppies. I've read that 8 weeks is best, then somewhere else it says that 12 is great. Is there really one great time I should use as the cutoff? Is 14 weeks too old? The puppies are fully socialized to humans and dogs and live in the breeders house. I will be introducing the puppy in our house to a young child and a cat, if that information helps. Thanks!