I also am a single mom with 2 kids. One now is 28 and on his own, the other is 19 and still living with me. As they were growing up since they are boys seemed to have that in common,but little else. The oldest always was interested in girls and hanging out with his friends and the other just in staying home and learning about cars and video games. They too were constantly getting on each others nerves and mine. I know that having them further apart helped and being both male, but I have noticed that teenagers are still teenagers no matter what. Since you have a girl and a boy it would be even harder, because girls react to things differently then guys. Since your son is older you would think he would know better, but I know that boys mature later than girls so mature wise they are probably at the same level. I also know that you wish you could just give them a good spanking and tell them to go to their rooms for an hour and chill. But they are too old for that and I know at this age they probably would just stalk off and tell you where to go. Trying to find something they have in common is probably not going to happen, but if you can find something you all like to do try and see if you can all do it together. I know this will probably sound corney or I am out of my mind, but doing something together gets their minds off of teasing each other so much and on what you are doing. We have monopoly, we like playing cards and a few other things. If you can have a movie night or have a special meal together where everyone has to participate in getting all made is a nice way to get everyone to work together. I know they both have their friends and teens now would think you are from another planet, but doing things together lets them see you can all get along. I had a hard time with my 2, but we made it through. It is only a suggesstion, but it may help. See if they are willing to give it a try. I know everyone is busy and their schedules are probably not on the same page, but I think that if they want to help you at all they should at least listen to you. I know that them fighting with each other is their way of communicating with each other. They don't know how to say what they are really thinking so it gets into a " I can out do you" match. It was hard when your kids are 9 years apart and the oldest is already almost done with being a teenager. A 10 year old and a 19 year old don't have much in common age wise and are in two different worlds in the first place. but I did find that since the oldest was out most of the time anyway it was easier. I can see that having two teens in the house at the same time can be harder. I often wanted my kids closer in age so they could play together, and I also wanted a girl, but that didn't happen. So if you can get them together for one thing, maybe just maybe they will see that that wasn't so bad and might want to try something else togther. I don't know if that will work or even if it helped. I just wanted to tell you what I know and what worked for me. I know what is was like being a single mom and still am. I now have my youngest son working with me. We both go to the same job at the same time. So, now he knows what it is to really work. Good luck.