You've gotten some good ideas here, but the basics are that those pups shouldn't ever be loose with the stock!!!! You need a long line, and work with them one at a time, and Never off the line. Every time they do something you don't like, you have to have some control to stop it. Every time they do something, it is a lesson - good or bad, it's a lesson they've learned. If you can't control them, they can't be loose. Period.!!! None of us that raise working dogs allow the bad behaviors to be learned. Pups are either on a line, or penned up. It will take work, lots of it. They are doing what their instincts tell them, but you have to be able to control what they do and when. As others have said, two pups is a recipe for untrained, out of control dogs. They work for and with each other, rather than you. BC's are very receptive to training, but it has to be consistent and firm. They also (as others have said) are not guardian dogs. They are dogs that gather and hold stock - then learn to bring them to the handler. They will always revert to that behavior, given the chance. They may learn to mellow out, but shouldn't be trusted loose with stock until they're old and "chilled out".