I walk and dog sit for a 6 year old 'entire' golden retriever. In every other way he is a fabulous dog. He's very loving. Loves his walks, swimming in the sea. He's great with the other dogs I walk as well. It's just when it comes to meeting with other male dogs that are 'entire'... We've been having a lovely week together. And just now bumped into a fellow male golden retriever on the beach and he attacked him. The dog in question is 15 years old. He was no threat whatsoever. It was an open beach. Luckily I knew the woman and I managed to pull him off quite quickly and he wasn't hurt. But it's shaken me up and I feel so bad for this dog and the woman. I generally only let him off the lead when it's quiet. I won't take him on the beach if there are big dogs down there but it was quiet this morning. There was one lone dog walking with its owner towards us. I didn't recognise who the owner was until it was too late (that the dog was an un-neutered male). I know I should have been quicker at pre-empting it. I explained to the woman as soon as I saw her that they were both un-neutered and we had better pull them apart. She went up to them but said my dog had started growling and asked me to sort it out but by the time I got to him he was on him. In hindsight on a Saturday (busier) I should have kept him on the lead. In the 2 years I have been walking him he has been aggressive with 2 dogs. But his owner has said he has also tried to fight dogs when he's taken him out as well. I have said again to him that he needs to be neutered. What other suggestions can you give other than keeping him on the lead? I won't let him play with strange dogs anyway just in case of this behaviour occurring. He's very close to my dogs, for 2 years he has not so much as barked at them but they are all neutered. Im not sure how to convince the owner that getting him 'done is the right thing.