You are suppose to teach them to speak then you can teach them to stop barking saw the UK trainer on Animal Planet Its Me or the Dog show do it.
How old are they??? how much exercise do they get??? are they litter mates??? Is their a puppy class you can take them too or an obedience class??? what breed of dogs are they some breeds are more yappy than others.
Hope Winnie are Shredder are doing good!... There many methods that you can do to solve the barking problem. You can enrol them in dog obedience class or you can also use some gadgets like remote trainer or collar, just make sure you use these tools properly.