A successful show career or years of breeding does not make a responsible breeder!
A responsible breeder is one that health tests and is proud and eager to show a puppy buyer their certificates.
Check for yourself the age of both Cavalier parents and their health certificates. No responsible breeder would be breeding Cavaliers that are less than two and a half years old.
There can never be any guarantees when you buy a puppy, even one from the very best of breeders, so be sure to take out insurance as vet fees can be very expensive.
If you buy from a dealer that sells ‘puppy farmed’ dogs, or from a breeder that does not try to breed healthier Cavaliers, you are rewarding them for not caring if your puppy suffers from painful inherited diseases.
Hard though it is to walk away, do not buy a puppy because you feel sorry for it, or because you want to rescue it from squalid surroundings. You make it worthwhile for that puppy farmer to continue breeding.