Improperusername posted a great link to a video series by Jean Dial called Put 'Power Steering' on your horse! New video series online.. If you want to get a good stop on this horse this series explains it far better that I can do here. A pelham or twisted snaffle won't solve her stopping problem for long and without the owner getting onboard with her training is likely to end up a lesson in frustration. Best of luck to you, there are no shortcuts in horse training that don't usually end up causing problems down the line.