Dog walk with big Ben (Caucasian x German Shepherd) in Northern Ireland

Ben's owner told me that he is reactive to other dogs, especially close to home and when he and they are on the lead. As well as reactive to sheep. A few trainers have been consulted, a prong collar was one of the suggestions...I have him on a slip collar and will try putting him in a sit when we encounter his triggers. #dog #dogs #doglife