Hi Lola is a 2 year old bitch, she is very friendly and playful and well socialised. She usually walks with my 20 year old son, but when I come on the walks, she turns aggressive to other dogs, even her friends! usually by barking them away, but today she actually attacked one of her friends because she went to come up to me. I always take dog treats on the walks with me and give them to her before we see a dog and after (if she was good) and I had just done this to a previous dog which was fine and then she done this to a dog she plays with all the time because it went to approach me and I said hello to it! How do I prevent this behaviour? She is usually very good, well trained and obedient. She would never take food until I tell her to take it, or walk through a door before me, she will obey all commands, but she just doesn’t want other dogs near me! She is fine with other dogs in the family, including my mum and dads dogs who we spend a lot of time with.