Hello! My 2 year old cane corso male has started to show dog aggression after we have put down our female dog who was 4 years old. He was very good and friendly dog, and she was the aggressive one (towards people and other dogs). After she died, he started showing aggression towards unfamiliar dogs, now he doesn’t even sniff them, just attacks as they approach. He is still very friendly towards people, and also very obedient, but his attitude has significantly changed toward other dogs when they approach. I would appreciate any advice on how to correct this behavior! I know that I have also been nervous after I noticed he is showing aggression, because I have lived for 4 years with very aggressive female (dominant-fear agressive female), so it has been hard for me to relax now when he is starting to show this behavior. Thank you all in advance!