I have a 4year old English bulldog who starting at about 2years started showing some aggression infrequently. Now I'm frightened to take him outside because he goes after other dogs and people, not everyone but definetly more frequent than ever before. He was well socialized as a puppy, never had a problem until he started getting older. At about the same time he stopped walking with just one person, will only go if at least two ppl are there. He is the biggest sweet heart when he's with his family, but now I am scared to introduce him to any dog or person, because sometimes he goes after them.

I have ordered a muzzle so I can take him out and try to correct his aggressive behavior without being concerned about him hurting someone else, but if anyone has any insight into why or other ways to help correct his bad behavior I would appreciate it!