Hi L.,
I can relate to the tried everything bit! I really think it takes a long time for these little ones to 'get it' with behavior stuff. I have found that pointing out the behavior with a couple simple words every time I hear it works for us in the long run. A simple 'no hitting' in a calm but serious voice gives the message that I do think they eventually understand!! I also ask my child to apologize for their behavior. Sometimes they will refuse and I'll let it go, but most of the time they will apologize. I also try to teach my other children to calmly say 'no hitting' or whatever, which occasionally works! My 5 year old has just taken on teasing and taunting his 2 year old brother, which drives me crazy. I have been saying the same thing to him a million times it seems, but I know he'll get it at some point and have learned more about what is socially acceptable and what's not. I wouldn't expect any real changes in the near future, but for us staying calm and using consistency in our message has been important and not giving up on the message that we want our kids to learn from all this.