I need help! My dogs are extreme chewers and I need something they can't kill! My boyfriend's border collie mix DESTROYED the Everlasting Treat Ball. He loved it...while it lived. (

5 days). I need something the collie can chew BESIDES the corner of the cabinets! Preferably something my babies can get in a smaller size too...but that isn't a big deal. HeLp?!?