Kids fight with each other because they need attention. The best way, but this is hard, is to give them undivided attention for as long as they want it. Then

Kids fight with each other because they need attention. The best way, but this is hard, is to give them undivided attention for as long as they want it. Then you have to figure out how to reward cooperative play and not reinforce either negatively or positively bad behavior. It's hard to do....