I`ll explain a little more...
This guy, lets call him Joe, the one that is making fun of Mike. Joe, has always seemed to have it out for Mike. Mike moved to the area about 4 years ago, mid-way through high school. Mike is a great friend, he's pretty crazy, lots of fun, and doesn`t like to make enemies, easy going type of guy. Joe, is a real smartass and challenges what a lot of our friends say or make fun of them if they make the slighest mistake. Quite a few of our friends have almost popped him in the nose, cause he is a real prick sometimes.
More and more, we have noticed that Joe keeps on challening Mike, on whatever he says and whatever he does. Mike just gets sick of arguing about everything he does and just trys to laugh along to the joke.
So, it has gotten to the point where he hasn`t been saying much lately, and has just been keeping to himself.
My theory is that Joe, from the beginning, felt that Mike was taking over his place in our group of friends and is trying to make Mike look like less of person than he is.